In September, Billie revealed that she is expecting her second child with fiancé Greg Shepherd. The couple are already parents to daughter Nelly, two - Sam's niece.
Gushing over her sister's baby news, Sam exclusively told Reveal she can't wait to have another baby in the family, but her own plans to expand her brood are currently on hold.
Speaking about Billie falling pregnant again, Sam said: "I'm so excited for there to be another baby in the family. It feels like we've just been waiting for Billie to make a pregnancy announcement."
Billie had quit TOWIE in August, a month before announcing her pregnancy, and explained her reasons for leaving were due to wanting another baby and focusing on her family.
Since she revealed that baby number two is on its way, many have speculated whether Billie will have a boy or a girl and Sam told us Billie is hoping for a boy - after seeing Sam with her baby, son Paul, nine months.
"She always says she wants a Baby Paul," Sam claimed. "But I've always imagined Billie with girls."
Despite being oh-so-pleased for her big sis, Sam added that as much as she would like to have another baby, Billie falling pregnant again hasn't made her broody just yet.
Sam explained: "Me and Paul want a big family, but our priority is to find a family home first. Once we do that, I think we'll definitely want another baby. I'd like four or five and Paul would like six!"
Fans will get to see Sam and Paul house-hunting in the second series of the former TOWIE star's reality show.
Sam first starred in Sam Faiers: The Baby Diaries, which documented her pregnancy and Baby Paul's birth, and will now follow that up with The Mummy Diaries.
In the meantime, Sam has been gushing over the prospect of becoming an auntie again.
She shared a photo of herself and Billie to Instagram and highlighted her sister's little baby bump. Sam told her followers: "Me & my beautiful sister. I am so excited to become an auntie again. Baby no.2 #blessed."
To read more from our exclusive chat with Sam, pick up your copy of the latest issues of Reveal, available to buy now.
Sam Faiers: The Mummy Diaries airs Wednesday 12 October on ITVBe.
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