The former Coronation Street actress looked pretty in pink as she attended an Instagram party with husband Ryan Clark on Monday evening (16 September).
Katherine, 33, announced her happy baby news via Twitter on 14 September, writing: "Ryan and I are overjoyed to announce we are expecting a baby! Feeling very blessed!"
The pregnancy announcement came a month after Kelly and digital analyst Ryan, also 33, tied the knot in Las Vegas. The couple didn't invite friends or family to the ceremony, instead preferring to keep the big day to themselves.
Other stars at last night's party included Alex Jones, Laura Whitmore, Ashley Roberts and Kate Middleton's younger sister Pippa.
More stars expecting babies in our gallery below!
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