Mary's sudden arrival has everyone in the family wondering what happened between her and Wilson. Only Mary knows and she's not telling. Her presence delights Annie, who goes out of her way to make her daughter comfortable, even offering her the converted garage apartment. But not everyone is happy to see her. Ruthie feels that Mary owes everyone an apology for the actions that led to her moving away.

Matt, Lucy, Simon and Ruthie are banished to the garage apartment after protesting Annie's decision to give the place to Mary, but then the roommates begin voting each member vies for sole ownership. Meanwhile, Eric and Annie are not seeing eye-to-eye on Mary's situation as she is now returning home and is wondering on what's next in her life. Robbie is nervous about meeting his new girlfriend's parents.

Mary and Lucy seek their parents for expertise in matchmaking and ask their parents to find new boyfriends for the both of them. Robbie argues with Joy about spending so much time together when she insists on seeing him right away. Simon and Matt are looking for girls using the Sam and David as adorable bait to attract women, but it doesn't go as planned. Robbie unknowingly becomes the key to finding Joy's missing younger brother Joseph when he finds a stray dog in the street that belonged to him.

Annie's father Charles shows up at the Camden household for a weekend visit as Ginger supposedly needs to get away for a bit. But Eric forgot to tell his wife about it and nearly everyone in the Camden household is too busy to spend time with the elderly man. So Grandpa Charles takes Simon to get his learner's permit for driving and they end up being the center of a televised police-pursuit. Eric lies to Annie about his plans for the day, which include a trip to Glenoak Hospital.

St. Valentine's Day delivers a few surprises for the Camden family. A grounded Simon is asked out by a senior. Annie's attempt to surprise Eric with romantic Valentine's plans backfires and results in a big fight. Mary discovers Robbie's plans with Joy. Lucy and Mary learn that Jeremy and Wilson both have dates for Valentine's. Matt seeks his fathers help as he wants to settle down, which leads him to seek out old girlfriends as to why they're no longer together. Ruthie is hesitant to go to a party because her friend tricked her into asking out a boy she's already going out with.

Annie frantically cooks Jewish dishes as the Camdens prepare to head out to a Shabbat dinner at the Glasses. Simon asks Matt and Sarah if he can bring his friend Morris to the dinner. Matt agrees to allow Morris to come to the dinner as he is half Jewish. Although, that does not go as he planned as he is not very knowledgeable about his faith. Lucy and Mary play sick to try to skip the outing so they can stay home with Robbie. While home, Mary flirts with Robbie. Lastly, Eric and Annie are unable to handle everything when they are shocked to find out during dinner that Matt is considering to convert to Judaism.