Jonny Byrne had been playing the drinking game known as 'neknomination' before his death.
The 19-year-old's body was discovered in the River Barrow in Carlow in the Irish Republic.
His brother Patrick has appealed to the public to avoid the stunt which involves people being challenged to post a video online of them downing drinks, then nominating others to do the same inside 24 hours.
Public health agencies have widely condemned the online craze and have appealed to young people to recognise the dangers posed by heavy alcohol consumption.
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The Good Morning Britain host paid tribute to NHS staff for "fighting as hard as Derek is to give us the chance to be reunited".
There have been scenes of chaos in multiple cities, from Denver to New York, writes Robert Moore.
Most areas dry and warm with plenty of sunshine and light winds.