It's slightly hard to grasp the fact that the man sitting opposite, in waterproof golf trousers sipping an iced-tea, is the son of America's commander-in-chief.
Dressed in a white open-neck shirt, navy V-neck sweater and hair slicked back, the 33-year-old could be mistaken for any one of the guests at the family's Trump International Golf Links and Hotel in Doonbeg, Co Clare.
Disarmingly polite, he asks where I would be most comfortable sitting during the interview and is concerned that one of his entourage hasn't eaten when our meeting eventually runs over time.
Far from the typical child of privilege you'd expect from New York's wealthiest, the only thing that gives him away as the son of Donald Trump is the ultra-confident gait, self-assuredness - and, of course, the fact that secret service men and gardai are outside the door.
He settles into the couch by a large open fire and looks out on to the perfectly maintained golf course he has spent the morning inspecting. As white waves from the wild Atlantic crash the coastline, a break in the rugged paradise gives him the opportunity to reflect on the biggest political battle in American history.
"They all got it wrong. Every single one of them," he says of America's liberal media. It's a remark delivered with the same satisfaction as if the victory was only yesterday.
"You know, we were a family who has never had anything to do with politics… so the learning curve was amazing."
The biggest lesson he learned was "how dishonest and disconnected the media were from the American population. I also realised how mean the process is. It's something that is not spoken about enough".
"Mean," he stresses again.
"Politics is a mean game. I always said real estate is the most cut-throat industry in the world - but it is nothing compared to some of these politicians."
How does it make him feel when he sees the amount of vitriol directed at his father and family?
"I used to get bothered by it but honestly, now? I just shake my head because they all got it wrong. [The American liberals] totally misread the sentiment of the United States because they are so detached from the people of our country. Now it is like they are doubling down because they are so furious they got it wrong."
He goes on: "And it wasn't just by a little bit. The entire map of the United States went bright red [minus a few states] and they are so outraged that they have almost actually gotten worse."
Of all the criticism, what has been the most hurtful?
"Listen, I am an adult and I also was the first one to jump on stage and stand shoulder-to-shoulder with him [my father] so shoot all the bullets you want at me. I put myself out on that stage and I put myself into that arena and, hey, if I am going to do that, then I better also be willing to take the scrutiny. But I think what is more disturbing is where they attacked Tiffany.
"A 22-year-old girl who is coming into the world as a young professional, who has just graduated from college. Where they attacked [Barron Trump] a young boy of 11 years of age who is just a child - when they go after him with hatred and disrespect… there is an unwritten rule: you do not attack the children of the President of the United States. You don't attack children in general. Let's not even talk about us - you don't attack children in general. Truthfully it's sickening."
He says: "They [had a go at] a [then] 10-year-old kid. It's tough. I'm a grown-up. I'm a big boy. Attack us."
He describes how he has learned to live with the abuse: "You are forced to develop an armour and that's fine. I think we do it very well. You learn to ignore it. At the very beginning, you will be attacked for some nonsense and you are worried about it, but if you are concerned about every sensational blogger who is trying to get a couple of clicks, who is totally irrelevant, and no one reads their column, and they try and write some sensational story that is grounded in zero facts to get a couple of clicks - if you are worried about every little nonsense blogger, you wouldn't sleep at night. You just wouldn't. So I think what you do is that you start throwing out the bad and embracing the good."
Rather than being put out by people approaching him, he says it is the kindness of supporters that gets him through.
"I'll be walking down the street and I'll have 100 people come up to me and say 'tell your family to go all the way. Your father is saving this country. Your father is the greatest'. There will be pictures and they will give me hugs. You wouldn't believe the thousands and thousands of times a week I have heard that 'my entire family are praying for your father and for your family'.
"So for every little one blogger who is out there writing some sensational article, you have 100 people… [saying] 'Thank you for the sacrifices that you have made collectively, as a family', and I can tell you this vastly, vastly outweighs the other - especially knowing that they [the detractors] got it wrong the entire time."
What is the one thing that is said which hurts his father the most?
"The falsehoods. He is the one person who did not need this job. He is a man who has achieved every aspect of success - wealth, family - in fact so many people often come up to me and talk about him and the concept of the American dream. He is the epitome of the American dream."
We talk about rock stars and how some felt they would have some weight because of their celebrity status. "Cool isn't transferable," he says.
Bono had a lot to say about Trump during his tour. How does he feel about Bono's remarks that his father has run away with the American dream?
"The American dream was running away very, very quickly. I think Bono got it exactly wrong," says Eric, before launching into an impromptu speech that would make his father proud.
"When you lose 70,000 factories since 2001 when Bill Clinton signed NAFTA - that's the American dream running away. When you have 96 million people in the US out of the workforce - that's the American dream running away.
"When people in the United States haven't gotten a pay raise in 15 years, that's the American dream running away. When you have an education system that is ranked 30th in the world - that's the American dream running away. When you have African-American youth in inner cities that is over 60pc unemployed, that's the American dream running away.
"In all fairness, it is very easy for Bono to say that the American dream ran away as he sings from a stage for $5m a night. I mean, give me a break!"
He adds: "I have nothing against Bono. I don't care [that he deferred his album following Donald Trump's presidential win]. I just think these celebrities are so detached from the realities of the world."
One Irish celebrity the Trump family do have a lot of time for, however, is golfer Rory McIlroy. Having played a round at Trump International in Florida with the president, Rory came under criticism online.
When asked for his response ahead of the US Masters, the golf pro said he would "think twice" about playing with President Trump if he received another invitation, given the amount of vitriol he suffered.
Eric says he can see why Rory would feel the heat from trolls and is ready to come to his defence.
"Rory is a buddy of ours. Rory is a great guy and an incredible athlete. And, hey, if you played with Hillary [Clinton] and she had won then he would have gotten backlash for that as well. That's the nature of politics. It is what it is. But do you know what the great thing is? He [my father] is not a politician so it doesn't matter - they can still go out and have a fun time together."
He continues: "No matter what side it is with, you are always going to get backlash. You are going to have a few people who have nothing better to do than to sit behind a computer and send a mean tweet. It's unfortunate, but it's the nature of the game."
Describing the golfer's relationship with the Trump family, he says: "Rory is an amazing guy. He has been a great friend and… we have gotten to know him very, very, very well over the years. And, by the way, he has been an amazing ambassador for Irish golf and he has done a lot for charities in Ireland. He's just a good guy."
While on the subject of golf, I raise the fact that his father has been criticised in recent days for playing 16 times since his inauguration. Eric says his father uses the game to de-stress but there is also another good reason for it - professional bonding.
"You can sit with somebody in a golf cart where there might be cultural differences and language barriers and have a good time and build a friendship in a way that you could never do sitting across an office table from someone - and I think being able to go to Mar-a-Lago [Trump's Florida estate], it is my father's Crawford, Texas."
He explains: "Crawford was George W Bush's ranch and Bush brought foreign leaders from all over the world [there]. He would go down to the ranch and they would drive a truck around and they would have fun and they would eat and that was his way of bonding.
"Mar-a-Lago is an amazing estate that has been a very effective tool for [my father] to go down and get to know somebody while not sitting - no different to you wanting to sit next to me on this couch today - not sitting across a wooden partition, which instantly makes a relationship more strenuous."
He explains: "If he can befriend people and find common respect, common ground and friendship - if you can have a good time together - then you are always going to see somebody in a very different light than you would with this kind of a relationship [he points to the wooden table] or a relationship over the phone, and that's an immensely powerful tool."
When I ask about his own relationship with his father he says: "What people don't see is that he has a heart of gold. There is no better father in the world than my dad."
Can he still talk to him as frequently since he became president?
"It's probably less now but we still speak a lot. If you are in the middle of a health care fight - he has the biggest topics in the world on his mind - then you have a little bit less time for casual chit-chat. I still see him a lot, I talk to him a lot - I talk to him several times a week. I spoke to him yesterday, but when you are working on the biggest issues in the world…"
He muses: "Quite frankly I feel guilty making small talk about nothing when Syria is going on. But he is still the greatest dad in the world."
What was it like growing up with Donald Trump as his dad?
"There were a lot of construction sites. I used to walk construction sites with him all the time. We would walk through whatever they happened to be building and there would be concrete pouring down 10 feet above your head. We would walk around with our little hard hats on crooked. I got to follow [my dad] around on the biggest Lego sets in the world. The tallest buildings in New York city, the casinos, we followed him around these. It was the neatest thing in the world.
"I remember hopping up on his lap on bulldozers and they were demo-ing whatever it was and it was like 'hey do you want to drive through that wall?' and I was like 'Yeah! Let's drive through the wall! Let's drive through the wall'. And you would take the D10 [bulldozer] and just plough through things," he says, gushing like an awestruck child at the memory.
He says it was during these years that he saw a trait which would enable his father to one day win over the factory workers in the American electorate.
"I have seen it my whole life. He does a better job relating to blue-collar people than most blue-collar people, to the point that some people call him 'The Blue-Collar Billionaire'.
"Most of the time, a guy walks on to a construction site wearing his suit and people roll their eyes and say 'here comes the guy who sits in the fancy office!' But construction guys love [my dad]. You saw it through the election. All of the auto workers voted for him."
What is it about him that they relate to? "Maybe it's that directness, maybe that boldness, it's certainly the brand. It's something that is aspirational but I also think there is a coolness level to him."
Is he the guy they want to be? "Yeah, I think you're right. He is the guy that they often envision themselves becoming - and most of all he is approachable."
As a child he recalls how his father was "incredibly competitive at skiing". On family holidays their father encouraged competitive behaviour as the children raced down the slopes and would often pull the young children back as they raced ahead.
"He would be incredibly Type A [in personality]," says Eric. [Type A personalities are more competitive, outgoing, ambitious, impatient and aggressive.] "I think we are all incredibly Type A."
Does he feel pressure to succeed under his father? "Yeah, listen, I think we have incredibly - more so now than ever before - we have incredibly big shoes to fill.
"But at the same time, I think we are the most fortunate people in the world. We have been given a platform on which to do amazing things and they come in all sorts of forms, such as philanthropy, like the work I have done raising money for children with terminal illness as part of the St Jude charity. But that's only one area where we can do a great job."
He describes how his father feels the family are connected to him as representatives of America.
"Quite frankly, I think he uses this term, [we are] the first family. I think [we are] ultimately representing something for a country. He, as commander-in-chief, is a representation of America. And I think we, as members of his family, we too become a representation of our country and we don't shy away from that."
Despite vast wealth and a privileged upbringing, the Trumps are known to have raised their kids with a strict mindset. From a young age, Eric remembers his father coming into his playroom and listing off the golden rules.
"At this stage I was only going to kindergarten and he would come in and say: 'Kids! No drinking, no smoking and no drugs.' And I was like 'Dad, 'what is drinking? What is smoking? What are drugs?' I was only six years old, playing with my Tickle Me Elmo at this stage," he laughs - and then his voice turns serious - "And then he would say: 'And by the way, you'd better get good grades'. Then he would give me a kiss and I'd run off to school."
Was he a physically affectionate dad?
"Incredibly, and he still is. With Don's kids and Ivanka's kids, he grabs them and he picks them up and gives them a big kiss."
Has he ever seen the famous alpha-male show 'emotion'?
"He is pretty good about keeping his emotions in check - everybody wears it a little differently. There have been moments after the win on November 9, and then obviously inauguration day, where you can see the gears turning and you can see… wow, there's something special… you can see it in somebody's eyes when they are blessed by something that has been achieved."
When do the softer moments come through? "I think it comes out around family. I see my sister's and brother's kids jumping on golf carts with him - a process like this certainly makes you even closer. What was accomplished as a small collective was beyond anybody's dreams. We were always called 'the next generation of Trumps', meaning Ivanka, Don and I, and now you are seeing the next, next generation, which is Don's kids, Ivanka's kids, and my soon-to-be kid [his wife Lara is expecting their first child]and they are running up and down the hallway of the office and it's a lot of fun.
"It keeps you very close as a family. But hey, listen, he is a tough guy and he can be a fighter when he needs to be. One of the reasons America elected him is that he is a fighter and there is no one that has more backbone than him."
Eric describes how his father taught his family about work and the value of a dollar.
"My dad had me on construction sites with a sledge hammer in my hand when I was 12 years old and obviously at that age I was making less than the minimum wage.
"My wife and I bought a house a couple of years ago and I went out there a couple of weeks ago and I built out my entire basement. I did all the electrical work, all the sheet rock, all the crown and the base board.
"I was wiring the chandeliers and my wife comes down and she says 'you're going to kill yourself' and I was like 'honey, I grew up doing this. This is what I did every single summer.' I worked for the guys who were building for us and I had the worst jobs of all.
"And believe me, when my kid is 10 or 11, they are going to be up at 5am and they will be out there mowing the greens and they will be out there with leaf-blowers and they will be making a couple of dollars doing it.
"[My dad] made us work, which gave us the building blocks for later life and helped us to learn the value of a dollar. Because if you work so hard all day and you make 20 bucks and feel dead at the end of the day, then you are lot less likely to take that money and buy a six-pack of beer because it is not worth it.
"It puts money in perspective as opposed to the opposite where people are out dancing on tables in the middle of the night since they were teenagers. We wouldn't have been allowed. We have never been that type of family. At the end of the day it's just not who we are. We work incredibly hard, we are the first people in the office in the morning and we are the last to leave. We work hard and represent the family well and that has a lot to do with him.
"I think the worst thing you can give a Type A child is a lot of free time."
What's the best bit of life and business advice his dad has given him?
"To do what you enjoy doing. I do 250,000-300,000 miles a year. I do more travel miles on a plane than any human being in the world. I am more than willing to come over to Ireland for 14 hours and then fly back if I need to - and you simply couldn't live our schedule if you didn't love it, if you didn't wake up every day excited. It would just run you into the ground."
The best personal advice his father gave him, he says, is: "Loyalty. He is the kind of guy who is immensely loyal to a fault."
And on the flip side he says: "He never forgets disloyalty. There are a lot of people who are on the middle of that bell curve but he is on one side or the other. He would give the shirt off his back for someone who was loyal and he would give the shirt off his back for his family."
One notable influence that helped to shape Eric and his siblings was the fact that the Trump kids, Ivanka, Eric and Don Junior, were reared with the help of two Irish nannies, Dorothy Curry from Cavan and the late Bridget Carroll from Co Kerry.
Eric describes how Dorothy, in particular, proved to be a vital nurturing force in his own life.
Speaking about Dorothy, who continues to work with the family, he says: "She is a second mom to me and a really amazing person.
"I used to come to Ireland for some of my summers and I would stay with her for a couple of weeks in her family home in Cavan. I have amazing memories from that time.
"I always loved fishing, I still do, and I used to love catching trout in the river. I remember going to the Slieve Russell Hotel [to swim in the pool and play golf]."
On flying out of Belfast he says: "I remember the old days where you were driving through checkpoints with people with machine guns.
"Fast forward 15 years, I was looking at projects in Belfast. We looked at the Titanic Quarter but we never decided to go for it because we settled on Doonbeg - and so in a certain way for me it was a little emotional because, while I am not Irish by blood, I kind of feel like I am Irish by blood [because of Dorothy].
"When we bought this place I called her up and said 'we just bought this amazing property in Clare called Doonbeg'.
"She is one of the nicest, most innocent, people I know and she was the greatest mother figure in the world. Obviously my parents worked very, very hard, but Dorothy was just always there and she came in at a very young age to take care of us."
On the difficult times he went through as child, he says, she was there for "more of those than I can count".
"Dorothy came in when I was probably less than a year old and took on that role and now she has known my mom for 30 years and my mom and herself are still inseparable. She's a massive part of the fabric of our family. I mean quite frankly she sacrificed her entire life for mainly myself, but really the three of us. She never had kids. We were her kids. So we were very, very close and still are to this day.
Illustrating their bond, he says, "She was part of the group. My wife is pregnant, and when we announced it and called the family, she is pretty much the only person outside the family (she's inside the family) but who is non-blood, that knew at the same time.
"So I feel like I have a lot of Irish heritage in me based on her, based on the fact that I was coming over here with her every single summer. And, again, it wasn't like I was going to Dublin and staying in some hotel. I mean this was real Ireland. She would take a car and we drove all over Ireland together - it was a lot of fun."
When I ask about Brexit he is slow to weigh in. "It is such a personal decision for a country, which is not only based on fact but which is also based a lot on emotion, on nationalistic pride.
"Someone might say 'Why is he, from the US, opining on issues that are so important to the fabric of this country?' I find the independence referendum in Scotland fascinating. I have projects there and I understand the issue as well as anybody, but at the same time I can never pretend to try and mirror the sense of nationalistic pride and the emotional side of it because I don't understand that."
But from personal experience, he is happy to comment on one possible outcome:
"Ireland is arguably - and the UK in general - is America's closest ally in the world, hands down. It has been for a very, very long time. We won WWII together, against the worst evil. Our alliance is strong. Our leaders and the friendships that they have has gone back so far. The UK's best leaders, and Ireland's best leaders, and US leaders - they have had a connection which has always been inseparable. "And I can tell you, while I have nothing to do with the administration, I can tell you the bond between Ireland and the US will be the strongest it's ever been before.
"I can also say pretty definitively - personally speaking, I am not talking about the stance of the administration - but I would prefer not to see borders back in the country. I think it would probably set the country back many, many years.
"I remember crossing borders with people with machine guns - I would not like to see a time where we would go back to that."
One other area of world affairs he touches upon is a story which is dominating current headlines. Only hours before our meeting, his father tweeted: "North Korea is looking for trouble. If China decides to help, that would be great. If not, we will solve the problem without them! U.S.A."
When North Korea's president Kim Jong-un threatened to nuke US war ships, President Trump announced he would send in an armada.
"We have the best military people on Earth," he says. "[Kim Jong-un] is doing the wrong thing."
Speaking about his father's role as commander-in-chief he adds: "I think the world will be a safer place because of him because he will actually show real leadership and he will take action when action needs to be taken, when others haven't been willing to in the past.
"If the other night [in Syria] was any test of that - when children were being gassed - I think he did an amazing thing and one of the things he has been praised so widely for is his decision making."
No one has been able to solve the problem of North Korea. Does he think his father is the man do it?
"Yes. I think he will. Quite frankly, I don't think anybody tried to solve the problem [in the past] and one thing I can say, and who knows what happens, again I have nothing to do with the administration, I don't discuss these things with the administration, no different than I don't discuss business with him, but he is very firm and he will not jeopardise the safety of the United States or the rest of the world for a lunatic who is in power. And he will do what it takes.
"He will make the right decision and we won't be prodded and he won't be intimidated and he will show leadership - that's the best way of saying it. I sleep well at night knowing he is the person who is making the decisions. I sleep safely at night knowing that he is in charge."
As we wrap up it's clear to see Eric is eager to get a round in before heading home. And it's no surprise. Named top resort in Europe by Conde Nast Traveller, Doonbeg has undergone a remarkable €4m transformation under renowned golf course architect Martin Hawtree. The two-year project includes a full renovation and reshape of each green, fairway and tee box and the construction of practice facilities.
Still, one of its biggest draws remains the chance to play against one of the world's most magnificent golfing backdrops of wild rugged landscape on the remote white-capped bay in west Clare.
As he makes his way out to the course he is willing to bemoan one thing about his father. For Eric's 12 handicap, his father plays off a two. When I ask if his father will come to Doonbeg to join him for a round, he says definitely - in the next four to eight years. As can be expected from a Trump, he is already thinking about a second term.
His father is famous for making his feelings known on social media and Eric is no different. Doonbeg staff wait to see if he is happy. Before taking off, a picture of the five-star resort goes up on his instagram account to over half-a-million followers. Reflecting on general manager Joe Russell and his team, the caption reads: "Great being with our team. I am so proud of the property and of all of you."
And it may have been the wild, west of Ireland winds, but I could have sworn I heard a collective sigh of relief sweep over Co Clare at the news of one more happy customer.