When Dave notices how nice Hillary has been to him recently, he is certain it's because she's having sex with someone. However, Mike spies on her and confirms that Dave is actually wrong. Dave then comes to the conclusion that she's smoking his pot when he notices his stash has gone missing. As he's confronting her about it, though, he accidentally tells her that it's his, but quickly tells her that it's not really his - it belongs to Vicky's mother, Betty, that she uses for medicinal purposes.

One of Hillary's friends gets breast implants, so now, Hillary wants to get implants, too. However, both Dave and Vicky won't let her do it, as Dave tells Hillary that it's what's on the inside that matters, not appearance. His advice is then tested when he meets Larry's new, overweight, unattractive girlfriend, Marla. Now, he'll have to figure out how to tell Larry that he can do better without going against what he told Hillary earlier.

Grandma Betty comes over with her new boyfriend for dinner with the family. However, soon, Dave finds out that she is spending a lot of money on him. Fearing that he'll lose his future inheritance, Dave accuses Grandma Betty's boyfriend of being a gigolo in order to break them up. Meanwhile, Vicky and Dave devise a plan to break up Hillary and Keith by showing Hillary how hard it is to raise a baby. Then, when Larry shows interest in baseball cards, Dave encourages him... until he learns that Larry is using the information to sell his cards on eBay.

Dave and Vicky decide to give Hillary the car she wants as long as she agrees to sign a contract so they can completely control her life. She reluctantly signs, but Dave and Vicky realize they may have gone too far with the restrictions. Meanwhile, Larry goes against the "bros before hos" code and dates Mike's ex-girlfriend, Heidi.

Vicky's mom Betty and her boyfriend Sid announce their engagement and upcoming wedding in St. Martin and invite the entire family to join them. But when Sid goes too far with a stripper, Dave wonders whether or not to tell Betty and risk losing the free trip. Meanwhile, Kenny goes on a date with an ex-boyfriend of Hillary's, so Dave has an awkward conversation with him about gay safe-sex, while Hillary worries she may have a knack for turning men gay.