Penny's mom is a criminal mastermind.

As messed up as Penny's mom was, her plan to get Penny back by making Wilona look like an unfit mother was pretty clever and diabolical. Like seriously. She must have been planning that out for a long time, and things would have gone according to plan if it wasn't for the tape recorder. Causing chaos at the party, creating so "evidence" that Wilona was an unfit mother and having everyone arrested, etc.

Also, I feel kind of bad for Wilona. First, it was Ray who claimed to change his ways (only to be a creep who tried groping Thelma). And then in "A Matter of Mothers", her new boyfriend Jeff turns out to be a backstabber who is secretly working for Penny's mom, lol.

Poor Wilona can never catch a break with the shitty relationships.