Frankie, who is expecting her first child with footballer fiance Wayne Bridge, excitedly told of her news this afternoon on Twitter (8 July).
Describing her bundle of joy as a "little dude", Frankie shared a photograph of all the boys' clothes she has already bought ahead of her October due date.
Among the pile was a little pair of red Converse trainers and a blue zip-up babygro, which could actually pass for a trendy onesie!
Frankie gushed: "Having so much fun getting my little dude's clothes together! A little boy to add to the @thesaturdays crew! Can't wait to meet the cheeky monkey!"
Rochelle Humes and Una Healy already have daughters, so Frankie's son will add a new dynamic to their group!
Yesterday, Frankie was pictured in a drop hem maternity dress while on stage with The Saturdays.
We wonder if her little man will be a singer like his mum or a pro on the football pitch like his dad?!
Did you guess Frankie was having a boy? Tell us below, as the best comment from across the website each week wins £50!