The mother of a little boy who drowned along with his father in a shallow stream had previously lost a partner in tragic circumstances.
Three-year-old Tyler Joyce and his father Sean Sweeney (36) were found dead on Sunday at the boundary to the Ashington Estate in Finglas.
Tyler's devastated mother, Pamela Joyce, has known tragedy - her then-partner Lee Kinsella was murdered in front of her nine-year-old son, Ryan, in 2006.
Ms Joyce was living with Finglas man Mr Kinsella (30) when he was gunned down.
He was fatally injured when shots were fired through the front window of his home on Ratoath Avenue.
His family believe the shooting was the result of a feud with a gang he had confronted after they crashed a stolen car into a vehicle he and Ryan were sitting in 18 months before his death.
He saved Ryan's life by pushing him out of the way of the bullets.
Some of Mr Kinsella's siblings later went on hunger strike in the hope that justice would be done.
At the time, Ms Joyce revealed just how traumatised her son was, saying he had become angry and was suffering nightmares.
"His death has really affected him. He can't sleep, he has become aggressive and is scared when he hears noises in the house," she said at the time.
"They have killed Lee and destroyed Ryan's life."
Tyler was with his father when they were found in the stream near the Royal Canal at around 3pm on Sunday.
Gardai suspect they may have fallen when taking a popular shortcut through a broken railway fence from the Ashington estate to their home in Finglas.
"Sean was a lovely, lovely chap, anyone would tell you that. We are deeply upset," said a neighbour of the Sweeney family last night.
Local people yesterday left flowers and soft toys at the foot of a tree near the scene of the tragedy.
Teddy bears, Easter eggs and colourful windmills were among the items.
"To our little brave boy Tyler, you will be sadly missed. Please angels mind him and keep him safe," one card from a family member read.
Childhood friends of Mr Sweeney also laid flowers at the scene and left cards and messages paying tribute to him.
A garda spokesman said the deaths were the result of drowning, which was determined in post-mortems, but it is not yet known how long the pair had been in the water.
The incident is being treated as a tragic accident.
Irish Rail confirmed that a work crew had fixed the fence just over two weeks ago, on March 12, but it was broken again in the meantime, allowing Mr Sweeney and Tyler to use the shortcut on Sunday.
"We repaired this fence on March 12. It is an area where there is frequent interference with the fence and we have fixed it numerous times," a spokesman said.
He added that the damage was discovered by a line inspection team earlier this month.
Irish Rail will be consulting with Dublin City Council about future plans for the area.
"We will have talks to establish if anything can be done to make this area more secure," said the spokesman.
Local people told the Herald that the shortcut is used regularly, especially by younger people.
Labour councillor Brendan Carr said he had known the area since he was a child.
"It appears the fence is meant to prevent people getting on to the railway line," he said.
"It's time for Irish Rail and Dublin City Council to come together urgently and replace it with a high wall as a permanent safety measure."