The Camdens are surprised by the arrival of Mary with her new guy Ben and his cop brother Kevin, and with her new flight-attendant job that enabled their cheap flights. While Lucy gets close to Kevin, Eric still obsesses over Matt's secret and Robbie and Ruthie still help keep it. Eric neglects his counseling appointment with the elderly Tallridges whose adult son Jerry has 'suddenly' moved out, yet that's just what will inspire him.

Preparations for Matt and Sarah's wedding are being made and things aren't going the way Eric or Annie planned. Matt decides he will convert to Judaism after a discussion with Sarah's dad who convinces Matt that he can convert on the wedding day much to Eric's dismay. Annie panics when Sarah's mother tells her to expect 100 kosher guests to her backyard pot luck dinner. Ruthie and Simon begin to resent Robbie being in the house. Ruthie wants her bedroom back forcing Robbie out now that Matt will be moving out and Simon gets upset that Matt chooses Robbie to be his best man and Sam and David call for Robbie instead of him. Lucy gets upset that Kevin won't come to Glen Oak for Matt's wedding and Ben decides to propose to Mary after Mary starts giving him the cold shoulder. Eric and Sarah's dad the Rabbi go head to head and it seems Matt and Sarah's wedding won't go ahead after all.