It was diffcult to tell who was Cheryl in a picture Tweeted by Nicola as guests all wore Cheryl Cole masks.
But the birthday girl wore a strapless floral play suit for the celebration and her hair in an up-do.
Black Eyed Peas star Will.i.am is also in Sin City and Cheryl partied at XS nightclub where he was a guest DJ.
'Erm... few questions!! Who am I? Where am I?? Why am I?? What am I? @NicolaRoberts @KimberleyJWalsh,' Tweets Chezza, whose ex-husband Ashley, 31, in on holiday in LA.
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Footballer Ashley Cole is 'gutted' about missing a crucial penalty for England in the Euro 2012 quarter-final and has jetted out to LA.
