The former TOWIE star turned yoga instructor returned to work last month, so time with her adorable son is even more precious than ever.
On Saturday (19 September), the Essex-born star wore a white top - risky with a young baby! - with black sleeves, teamed with ripped black jeans for a bite out with her son.
Arlo, dressed in a cute blue babygro with white cloud design, didn't quite manage a smile for the camera - but looked the spitting image of his daddy, footballer Andy Carroll.
Alongside the snap, Billi wrote: "Saturday Lunch With My Pickle #MyBabyBoy."
Later, Billi shared another heartmelting snap with the little tot.
In the photograph, she is holding up her son for a kiss.
In the accompanying message, Billi gushed: "My Everything My #MyLittleAc."
While lunch with mummy didn't quite raise a smile, it's obvious that baby Arlo LOVES bath time.
In black and white snaps from his baby bath, Arlo can be seen beaming at the photographer surrounded by bubbles and bath toys.
The proud mummy wrote: "I Love Him So Much #BathTimeFun #BathBottleBed."
Billi quit The Only Way Is Essex back in May 2013 to open her own Bikram yoga studio which has been a massive success.
She and her footballer fiancé welcomed their first child together on 15 June.
They became engaged in November 2014 when Andy popped the question over a romantic dinner in Rome during a holiday to celebrate Billi's birthday.
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