Baby Billy Peterson is Shubie and Nat Peterson's baby son. He is also the younger brother of Susie Peterson. He first appears in the episode "Goo Goo Gas."
Billy is a light yellow fish, with blue eyes and one tooth. He wears spiky purple headgear and a white diaper. He also likes to suck on a pale-red pacifier.
Role in series
"Goo Goo Gas"
Billy is seen with his mother, Shubie, at Barg'N-Mart, sitting in a shopping cart while his mother shops. He is later insulted by Plankton, and Shubie takes him away from him.
His name is revealed to be "Billy" when Shubie tells him to look at Squidward while he is dancing in a monkey costume.
He appears with Debbie Rechid, who is hanging clothes, when SpongeBob and Stickyfins Whiting crash through.
Nat Peterson is revealed to be his father.
- It is possible that in the episode "The Getaway" Debbie has been babysitting him.
- It is possible that he is related to Baby Peterson, as they both have the same last name.