After reluctantly inviting socially inept neighbors Fred and Mary Ellen Doyle and their kids over for dinner, Paul and Cate are shocked when the entire Hennessy clan is asked to take part in the Doyles' daughter's wedding. Meanwhile Kerry neglects to inform Bridget that geeky Donny Doyle has grown up to be a hunk, and Rory takes a part in a play as a cross-dresser in order to meet girls.

Having learned that her sister Maggie is having marital problems, Cate is nevertheless not too thrilled when Paul invites Maggie to stay at the house. Meanwhile, Paul and Cate are impressed with how mature Bridget has become after they agreed to let her go out with neighbor Donny Doyle, who is home from the Naval Academy. Bridget and Kerry wonder if Kyle has ulterior motives when he befriends Rory.

The rivalry between Cate and Maggie comes to a boiling point when Maggie gets a sexy, new makeover and gives Bridget a water bra as a gift. Tensions between the Hennessy sisters mount when Kerry and Kyle begin dating, while Bridget's popularity takes a nosedive after she dissed her friends for Donny. Paul becomes concerned when he finds an empty pregnancy test kit.

Bridget finds her popularity waning because of her exclusive, long distance relationship with Donny, while Kerry's social status skyrockets because of her relationship with Kyle. But Bridget's eyes begin to stray when she meets new kid Damian. Meanwhile, as she waits for the results of her pregnancy test, Cate is stunned when Paul, Bridget, Kerry and Rory seem more concerned about how the baby could disrupt their lives than the blessed event itself.

Donny's parents ask Bridget to be a part of a video message they are sending Donny. They are shocked to discover that Bridget has broken up with their son on the tape. Donny goes AWOL to try and patch things up. Meanwhile, Paul is asked to help give a nickname to a neighborhood prankster who has been terrorizing the block, not realizing that the culprit may be living under his own roof.