The nightmare when a secret, irrational fear comes true
Buckleys now share sorrow well known to other families
They are the bitter-sweet images that form a part of every Irish Christmas - those poignant pictures from Dublin airport of emigrants, returned home to the bosom of their families. Back, safe and sound, allaying all worries that their loved ones may secretly have held for them while they were away.
To the anxious parents of young men and women keen to spread their wings, letting their loved ones go is a wrench, and seems fraught with unknowable and unquantifiable risks - even amid the knowledge that they are not alone and that this risk is relatively tiny.
But for some, all too tragically, the risk emerges as a real one and culminates in a call to the front door by sober-faced gardaí, or a phone call in the middle of the night that shatters lives in a heartbeat and forever.
And the unfolding nightmare on foreign soil currently being endured by the family of Karen Buckley, whose remains were found on a farm on the outskirts of Glasgow after going missing on a night out, is one that now seems all too-frequent.
In a statement read by Det Supt Jim Kerr, her father John said: "Marian and I, together with our sons Brendan, Kieran, and Damian, are absolutely heartbroken. Karen was our only daughter, cherished by her family and loved by her friends.
"She was an outgoing girl who travelled the world, where she met lots of people and thoroughly enjoyed her life. We will miss her terribly."
Friends raised the alarm last Sunday morning after the occupational therapy student failed to return from the Sanctuary nightclub in Glasgow.
It led to a four-day search that culminated in the discovery of her remains on High Craigton farm close to Lough Lomond.
Friends in Cork grieving for Karen recalled a quiet but popular girl whose aim in life was to help people.
Her death has brought back the trauma for other Irish families who have gone through a similar ordeal, in losing loved ones abroad.
Andrew Furlong, the father of Wexford student Nicola Furlong, who was killed on a night out during an exchange year in Japan in 2012, told the Irish Independent that he and his wife Angie had worried about Nicola when she initially left for Tokyo.
The DCU business and languages student was a homebird who had not wanted to leave Ireland but was studying at the Takasaki City University of Economics for the third year of her degree. She had attended a Nicki Minaj concert in Tokyo in May 2012 and was found dead in a hotel room the morning after. Richard Hinds, a 21-year-old musician from Memphis in the US, was subsequently found guilty of her murder.
"When they're leaving initially, you always have the worry that something terrible might happen to them," Andrew said of his daughter's trip abroad.
"You tell yourself that it wouldn't be possible that something might happen just because they're in a different country but because they're away it makes it harder.
"When they're in another country, you're hoping and praying that they will come back and walk off the plane.
"But you can't stop them from living their lives - you can't wrap them up in cotton wool," he said. The devastated father now looks at the world differently ever since his beloved daughter, who would 'light up a room', was snatched away from them. "I don't know what way the world has gone - if it was always that way or it's that we just didn't realise it because people didn't travel and so we didn't know about it," he said.
'Only people who had money behind them travelled in the 60s and 70s when I was growing up and going out into the world but now everyone is going to college and going off travelling."
But he acknowledged that the travel isn't the issue and that there is also an ugly element of chance involved, saying that Nicola had previously travelled to America on a J1 visa and had come to no misfortune.
Just today, the funeral takes place of water polo champion Conor Keleghan (20) from Coolmine, Blanchardstown, who died after getting into difficulties while kayaking on the Soca River in Slovenia.
Meanwhile, the parents of an Irish girl at the centre of a trial currently underway in New York have never been made aware that their daughter was allegedly raped in the Hamptons, while over there working on a J1 visa.
The woman, now 22, testified last Tuesday that Wall Street banker Jason Lee attacked her in the bathroom of his $33,000-a-month rental home in East Hampton on the night of his 37th birthday in August 2013, after meeting her with her friend and her brother at a nightclub earlier.
She claims Lee, who denies the allegations, followed her into a bathroom and shoved the door with such force that she fell to the floor.
Lee allegedly pinned her down while she struggled with him and raped her before she managed to knee him in the groin with force.
And in another court case currently being held in Australia, Barry Lyttle from Ballycastle, Co Antrim, has pleaded guilty to recklessly causing grievous bodily harm to his younger brother Patrick in a one-punch attack which left him in a coma.
CCTV footage showed the brothers jostling outside a nightclub in Sydney last January before Patrick (31) shoved his brother. Barry (33) responded with a single punch, causing his sibling's head to hit the ground.
Patrick was in a coma for a brief period but made what was described as a "fantastic recovery" and was released from hospital.
He has since expressed his wishes that the charges against Barry be dropped and pleaded with the court not to jail his brother, saying: "When my family is healed, I will be healed."
CCTV images, this time of Jill Meagher walking alone along a street in Melbourne, unaware of the menacing figure of Adrian Bayley coming along behind her, cannot be forgotten.
Jill, who had moved to Australia as a child with her parents, was working for the Australian Broadcasting Corporation and was on her way home after having Friday drinks with friends when she disappeared in September 2012.
Days later, her body was found in a shallow grave more than 50km away.
Bayley was arrested and charged with rape and murder and it recently emerged that he had 20 previous rape offences.
In the nightmare scenario, a small risk can nevertheless turn out to be a real one.