Conal McKee from Dundrum, Co Down died in Miami shortly after 6am on Saturday morning.
The 26-year-old had been in a coma since Friday, August 3rd.
The father-of-one had been living in Florida, where he had begun a new life with his girlfriend Kata and infant son Danny,
He had been living in the States for three years, having previously lived in New York.
A keen Gaelic footballer, he played full back for Dundrum GAC.
His parents still live in Dundrum and his brother Niall Rock plays for the village’s senior Gaelic football team.
An online fundraising page was set up by his family when he fell ill.
So far, it has raised $17,382 of the $20,000 goal.
A statement on the GoFundMe page reads: “Everyone that knows Con knows him to have a smile because every time he met you he always laughing about something! Never one to have a bad word to say this warmness always drew people to him. Having recently moved down to Florida to set up a life with his son 7-month-old son Danny and girlfriend Kata.
“During this difficult time, we are asking everyone that knew him and loved him to help out with donations to assist in covering growing medical bills and expenses. We are confident that in time and with consistent treatment Conal will return to the same goofy, happy and hilarious friend we all love.”
Dundrum GAC chairman Mark Fitzsimons paid tribute to his former player: “It is with the deepest sadness that we learned this morning of the death of one of our own, Conal McKee (RIP). We as a club are devastated. We send our heartfelt condolences to his family at this most difficult time."
South Down Sinn Fein MP Chris Hazzard extended his condolences to Mr McKee's family
"This is a heartbreaking time for Conal's family and the Dundrum community,” he said.
"Conal was a very likeable and popular young man who represented Dundrum GAC.
"My thoughts and the thoughts of everyone in South Down are with all the family and friends at this tough time."
It is with the deepest sadness that we learned this morning of the death of one of our own, Conal McKee (RIP).
Conal passed away in Miami, Florida, at 11:10am our time.
We as a club are devastated.
We send our heartfelt condolences to his family at this most difficult time. pic.twitter.com/UNBbJaztOG— Dún Droma CLG (@DundrumGAC) August 11, 2018
Really sad news from Florida that Dundrum’s Conal McKee has sadly passed away - a very talented young man he will be sadly missed by all at @DundrumGAC and the wider community. Thoughts with family at this terrible time #SouthDown
— Chris Hazzard (@ChrisHazzardSF) August 11, 2018
Almost three years ago the club played its first official game. We are saddened to learn of the loss of one of the team from that day Conal McKee RIP pic.twitter.com/kSv1aQpmwZ
— DundrumUnitedFC (@DundrumUnitedFC) August 10, 2018