Bah Bah Ling is the adoptive father of Francine Smith. The name "Bah Bah" is actually Chinese for dad. He is married to Mah Mah Ling. Both Bah Bah and Mah Mah Ling did not seem to be supportive of Francine as much as their other daughter Gwen, and Stan attributed this to the factor that Gwen is their natural daughter and ethnic Chinese, while Francine is not. However, in "Big Trouble in Little Langley", Stan is trapped in the burning house, Bah Bah rescues him, showing he does indeed consider him to be a genuine son-in-law. Bah Bah apologizes to Stan for not being more overtly accepting, but that since Stan is a good provider to his family and loyal husband to Francine, that he felt Francine is well taken care of and that Francine herself is a very capable and intelligent daughter, unlike Gwen, whom he feels needs more attention. Stan is glad that Bah Bah has accepted Francine.
Bah Bah interrupts a fight between Francine and Mrs. Yoshida to tell them that Steve is one of two finalists in the National Spelling Bee in "Spelling Bee My Baby". When Mrs. Yoshida inquires if the opposing child is a Japanese girl, Bah Bah responds in what could be construed as an affirmative leer. When Francine calls him on it, he points out that he was only answering the question.
Bah Bah is voiced by Tzi Ma.