The TOWIE stars joined friends and family at a party, where they proved their fun side by dressing in costume for a photobooth picture.
Billie posted a snap of their shenanigans to Instagram, adding the caption: "So much fun today at dad's birthday. #funtimes #family #photobooth."
We reckon Sam, at the back, is wearing a cowgirl hat, and Billie's fiancé Greg Shepherd (far left) is maybe going for some sort of flamboyant 1930s gangster look. But Billie? We really don't know! She does look though, doesn't she?
It seems that Billie and Sam organised the entire event for their father Dave, as Billie tweeted: "Amazing dad at dad's surprise 60th birthday party. We pulled it off, sis!"
Mum-to-be Billie and Sam appear to have had a busy – and glamorous – weekend, as each tweeted plenty of shots of themselves over the past couple of days looking very made up.
The sisters were out on Saturday to attend the boxing match between co-stars Lewis Bloor and Elliott Wright, looking incredibly glam, while Sam was also spotted wearing a racy little blue jumpsuit on a night out in London later that evening.
Bilie's not alone! More stars who announced pregnancies in 2014 in pictures:
Copyright: WENN Lexie Appleby/Future Image/Bridow/Instagram
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