Man City completed the treble last season after winning the Premier League, Champions League and FA Cup - and the celebrations were wild.
They became the first English side to complete the feat since Manchester United in 1999.
Grealish was spotted out partying for several weeks, Erling Haaland turned up to the club in his pyjamas and Dias threw up on someone's handbag.
But not just anyone's - Grealish's mum's handbag.
According to The Sun, the Portugal international had never drank alcohol before but went through with a promise made to the team.
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He told the squad that if they won the treble, he would do some shots.
However, the first one he did at a celebration party back in Manchester was not staying down and the centre-back rushed behind a curtain to vomit.
A source told The Sun: "Ruben felt unwell because of all the travelling he'd done.
"He moved a curtain and was sick behind it — but it turned out Mrs Grealish's handbag was there.
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"Ruben wants to do the right thing and find a replacement."
Ederson had initially told the story of Dias' unfortunate event last month, telling Brazilian outlet Globo Esporte: "After a very exhausting and incredible season, only United had managed it, of course we have to take advantage and let our emotions out.
"These are months of intense work. Who drinks, drinks. 99 per cent of the group drank it, enjoyed it.
"Many players ended up only on Monday. That's part of it. You have to enjoy the good times.
"The missing one per cent is Nathan Ake, there are others who don't drink, but they made an exception.
"Dias went to make that exception, but it didn't work out for him. Two shots and he blew it all out [laughs]. Coincidentally, it was all in Jack Grealish's mother's purse."
While Dias might reconsider ever drinking alcohol again, Grealish certainly enjoyed himself over the summer with a series of celebrations - and why not?.