The Boyzone star, 33, died after falling asleep on a sofa following a night out with civil partner Andy Cowles in Majorca at the weekend. It's reported that he returned to his accommodation after enjoying a few drinks, fallen asleep and failed to wake up again.
The couple are also believed to have returned to their holiday apartment with another man.
'There's no foul play involved and it's not suicide,' says family spokesman Gerald Kean.
'It's just a tragic accident is what we've been told and we're happy that that is correct information.
'There is nothing untoward, it's not drugs, we don't believe, it's not suicide, it's not murder, it's not a fight. That's what we've been told.'
A post-mortem is expected to be carried out on Tuesday and a funeral will be held later in Dublin, Ireland.
'At the moment it is not known how he died,' a police spokesman tells the BBC. 'There are no signs of suspicious circumstances.'
Stephen's Boyzone bandmates Keith Duffy, Ronan Keating, Mikey Graham and Shane Lynch arrived in Majorca yesterday.
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