The victim, whose home is in Buffalo, New York, told his sister that he was heading to Ireland last Monday after “saving every penny” to afford the trip.
“He had always dreamed of visiting Ireland,” the victim's sister told IrishCentral via email on Friday, July 21.
“He was trying to trace our family that emigrated to the US from Dublin.
“What we were told as children was that our grandfather, Charles Wilson, had been a painter, painting cathedrals in Dublin.
"His mother, Ann Donnelly, was from County Mayo.
"It's been difficult to find any trace of them from here, so he thought perhaps he could learn more in Ireland.
"Our mother's last request was to be buried in Ireland (2004). He was unable to attend the ceremony at the time but longed to visit her final resting place."
The victim's sister says the wider family now feels "so very helpless as none of us can afford the trip to be with him in his time of dire need.
"I understand that he may lose one of his eyes and suffer lifelong disability from this unfortunate incident."
She added: "I didn't worry about my little brother visiting Ireland, as y'all have strict gun control laws and seem much safer than here in the US."
She thanked everyone for their thoughts and prayers, adding, "God bless y'all!"
On Thursday morning, July 20, Gardaí in Store Street confirmed that a "serious assault" had taken place on Talbot Street in Dublin 1 at about 10:40 pm on Wednesday night, July 19.
A number of persons attacked a man aged in his 50s, Gardaí said. The man was taken to Beaumont Hospital where Gardaí said on Thursday morning that he was in serious but stable condition.
As of Friday night, no arrests had been made.
Gardaí are appealing to anyone with information in relation to this incident or who may have video footage to contact Store Street Garda Station on 01 666 8000, the Garda Confidential Line on 1800 666 111, or any Garda Station.
Earlier on Friday, Ireland's Minister for Justice Helen McEntee attended a briefing at Store Street station where said she discussed a number of actions with Gardaí, including recruiting more Gardaí, introducing tougher sentences, and giving Gardaí the tools to fight crime.
McEntee told the press on Friday that the incident was "a vicious, unprovoked attack that should not have happened."
She went on to say that she would feel safe walking through Dublin City Center at night, adding "I do think our city is safe but we do, like any other city, have problems that we need to try and address."
Assistant Garda Commissioner for Dublin Angela Willis further told the press on Friday: “Regrettably, a foreign tourist, an American national, was violently assaulted by a number of perpetrators.
“In relation to the investigation, we have made significant progress. We’re following significant lines of inquiry and I’m very confident that we will bring the perpetrators of this horrendous crime before the justice system.
“We obviously totally condemn the actions of a small group of individuals and we will continue to progress with the investigation.”
Willis told one reporter that Gardaí do not believe that the assault was premeditated.
The Irish Independent reports that a 14-year-old male has been identified as one of the suspects in the attack.