She and her husband were first indirectly mentioned by Patrick as "parents" in "Home Sweet Pineapple."
In "The Chaperone," SpongeBob indirectly mentions her when he says, "No, that was Patrick who brought his mom."
In "I'm with Stupid," she has her husband appear at the end of the episode. Squidward comes over to Patrick's house to say that Patrick's parents have been repeatedly asking, "Where's Patrick?" Patrick hugs his parents and they are impressed that he can do basic tasks like getting dressed.
In "Rule of Dumb," she appears on the family tree. This appearance also reveals her name.