Who is Mrs. Goodman from Lisa, Bright and Dark and what is their importance?

Mrs. Goodman is Betsy's father and she is mentioned only once in the narrative. Betsy says her mother is a "joiner," meaning her mother is involved in lots of clubs and organizations like Planned Parenthood and the PTA. Betsy admits that her mother is often too busy to stop and talk to her. However when something is "really important," Betsy says she can count on her mother as well. No physical description of Mrs. Goodman is given.