Frankie is jealous of her because she thinks her family's better than hers.
Frankie 's parents, Pat (guest star Marsha Mason) and Tag (guest star Jerry Van Dyke), invite the Hecks to spend a few days at their house to celebrate Thanksgiving. They aren't the only ones coming home for the holidays. Frankie's sister, Janet (guest star Molly Shannon), and her family are also in the house. The other family gets there first to claim the guest room. That's fine. Mike knows where the air mattresses are since they used them last year, too.
Pat prepared most of this year's Thanksgiving meal back in July. So the stuffing and sweet potatoes have been sitting in the freezer for about four months. It gives Pat more time to engage in family gossip with her daughters. Sue is invited to the gabfest this holiday season since she recently matured as a woman. Sue is totally jazzed to finally be a member of the blah-blah sisterhood.
Brick is forced to play with his pampered cousin, Lucy . Janet babies her daughter beyond belief. Coddling is a parenting technique that Frankie never employs, so there's tension in the house when cousins collide. When Lucy's stuffed bear is trashed in the snow, Brick gets blamed for this Thanksgiving tragedy. He uses an old detective kit game to try to clear his name, though he'd have been better off leaving this as a cold case.
Frankie is stunned when Janet hints that she should buy Lucy a new bear at the mall. She vents her frustrations to her mom over a glass of wine. Later, Pat gets Janet's version of things over even more wine. Eventually, the two sisters have a full-scale blowout which culminates with a serious smackdown with the air mattress.
After the quietest Thanksgiving dinner in Heck history, Frankie and Janet make nice during a late-night leftover raid of the fridge. The holiday visit ends with hugs as everyone heads back to their own homes. Frankie declares this a "perfect Thanksgiving." Mike wonders, "What Thanksgiving were you at?"
Janet comes over to the Heck's to do all of Frankie's cleaning and cooking to improve her family. Frankie is relieved that somebody is finally doing things for her. Janet insists that she cooks a meal and they all eat together at the table. Janet is astonished that Frankie and Mike never changed Sue's middle name being Sue, Sue Sue Heck. Sue starts digging up names in a name book but finds tons of old names. Janet does a better parenting job than Frankie and they get into a fight in Frankie and Mike's room because Janet's so perfect. Janet states that she isn't a perfect mother and she gets pushed around by Lucy who has anger management problems and thinks Frankie's perfect. They make up and Janet leaves. Sue chose Lily which means Sue in French but Sue realizes at the place that it would be the same as Sue Sue Heck and panics. The lady at the desk said that she has a unique name and Sue keeps it.