After going to the source, I recommend the following regarding Piggy's parents. Go to the Muppet Wiki and search for "Miss Piggy", then go to the "Family and Background" subheading. Once finished with that, click on the link to read the info on "Miss Piggy's Mother". There are a few fics here that refer to Piggy's mom as Hortense, though that's an unconfirmed fan-given name. Hope this helps.