Jay's ex-wife slash Claire and Mitchell's mother, Dede (Shelly Long), comes for a surprise visit to see the family. Apparently the last time they've seen her was at "the incident," where she made a huge scene at Jay and Gloria's wedding. She had to be Mitchell to get her invited, much like this time around she begs the momma's boy to get her invited to family sunday dinner for her to make her apology. Dede has a new boyfriend she wants to move to Canada with, but before she can move and be intimate with her new man, she must make ammends for the incident.
Meanwhile, Manny had his first sleepover where he was the first kid to fall asleep and had a goatee drawn on his face in marker. Jay convinces Gloria and Manny that the boy should go for revenge, so the little crazy bastard sets the kid's bike on fire.
Haley is trying to convince her parents to let her go to an overnight concert with her older boyfriend Dylan. Dede helps her cause and Claire agrees to let her go if Dylan comes to Sunday dinner and proves he's the nice guy that Haley claims.
All three plotlines come together at the family's sunday dinner, where Dede apologizes to to Gloria, who trying to set a good example for Manny to not exact revenge, accepts. Dede wasn't expecting an apology and was prepared to fight... so she goes for it anyways. The guys keep them separated (with Phil more than happy to jump on Gloria). However, it's actually Dylan who steps up and gives a speech to bring the family together. He then almost wins them over with his song written about Haley, until it mentions doing her. Man, he was so close to being able to do so at the concert until he did.