The TOWIE star, 24, took Nelly to work with her at Minnies Boutique this weekend, making her the "newest member of the team".
Going back into work for a photoshoot for their new autumn/winter collection, baby Nelly joined in the excitement - but, if the cute picture is anything to go by, she might have slept through it all!
The black and white snap shows proud mum Billie leaning over sleeping Nelly in her comfy baby rocker, surrounded by the staff at Minnies Boutique.
Auntie Sam, 23, can be seen in the background having her hair curled for the photoshoot, in which the sisters would be modelling the new season's range.
Alongside the photograph, new mum Billie wrote: "All of the @minniesboutique team on our autumn/winter photoshoot ... And of course the newest member to the team little Nelly #baby #fashionista."
The Only Way Is Essex star Billie also shared a selfie from the set, showing off her impressive post-baby body.
In a monochrome animal-patterned jumper dress, the pretty blonde showed absolutely no signs of the sleep deprivation that usually accompanies having a newborn baby at home.
She wrote: "#selfie on the @minniesboutique photo shoot ... autumn/winter #fashion #comingsoon."
Five-week-old Nelly has already become a TV star after appearing in the last series of TOWIE.
Sam and fiancé Greg Shepherd welcomed their first child together on 10 July.
Billie recently revealed she is hoping to get her bikini body back soon, but she already looks pretty good to us!
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