Kym's three-year-old daughter Emily is said to be the third bridesmaid.
It will be odd for Jack if Natalie Cassidy is a bridesmaid, as she plays his TV girlfriend in EastEnders, who he often has to snog on-screen.
Rows with the band
A few months ago, fans would've expected Kym's Hear'Say pals Suzanne Shaw and Myleene Klass to have been bridesmaids, but that's all changed since Kym left the band in January.
There were rumours that she really didn't get on with Myleene and left after lots of rows with the other band members.
But now the big question is: will the wedding reception be held at the Queen Vic or E20?