Robbie remains inconsolable since Mary left with Wilson. The Colonel figures she won't go to college but marry and be a mother to Billy, so he insists on a job, preferably in public service, but he nor Wilson are pleased she opts for the police or fire department. Lucy refuses to explain why she left the New York seminary, apparently after a break-up with Jeremy, and Robbie is parentally dissuaded as consoling company. Annie works out her pre-menopause frustration on Eric, and he takes it out deviously on model student Simon for just a bit of attitude. Matt loses his hospital orderly job, but soon gets another: in a free clinic with mainly teenage and young-adult mothers-to-be.

Robbie amuses sneaky cookie-thief Ruthie by nicknaming her Snookie and sets straight Lucy's far less flattering interpretation. Wilson diplomatically handles Mary's absurd blaming him for her failed fire department application after she set fire to the colonel's curtains. Despite Eric's continuous meanness, Simon acts most responsibly when a kid only he, not even a teacher, defended against school bullies mentions planning to shoot them. Eric confronts the supervisor of a firm's staff where 'pranks' extend to stealing a prosthetic arm an counsels his ex Merle on forgiveness.

Robbie offers to pay $200 rent for the garage apartment if it ever gets finished. However, the siblings all want it, so Matt is promised a switch with his room and the others are jealous. Billy clearly pretends to be 'really' sick to make Mary stay with him and perhaps become his mama. Lucy promises handyman Ray Rickey work on the garage apartment, but the crook fakes a fall and has a leech-lawyer waiting.

Robbie introduces Lucy to his friend Hugh, feeling she should date again, but gets jealous enough to separate them with lies. Matt stands up against the free clinic's staff and gets Hank to overrule Dr. Kent's diagnose-and-operate routine. Feeling incompetent as a waiter at Pete's Simon resigns, but he gets promoted because of his business-planning skills. Cued by Billy via George, Wilson and Mary (who is failing in firefighter training) realize it's time to decide whether to commit to becoming a family.

Insecure Robbie hides his budding rebound-affair with Lucy. Wilson is deeply hurt when he finds fickle 'bride' Mary kissing fire-department coursemate Ben Kinkirk. Simon doesn't enjoy bully-mate Rick's girl abusing him as excuse to dump him. Annie's flippant advice nearly wrecks pupil Christy Parks' parents' marriage, yet she resists help even from Eric.

Robbie and Lucy gather the courage to tell everybody about their affair, only to find they all knew and don't really care. Without the thrill of sneaking, their first date fizzles. Ben Kinkirk and Mary both pass the firefighters course, but their meeting on whether to celebrate with classmates messes up Mary's reconciliation with fiancé Wilson., and Billy's questions make Wilson decide against her plan to elope. Matt discovers that Hank and Julie are planning a divorce, and Eric and Annie try to find out why and see if they can help fix it.

Wilson is amused that all the Camdens call him after Mary's sudden return home, but wants her to tell them what happened. Robbie makes clear he's no longer interested at all in her or Lucy, having found a potential bride. The siblings however are furious when their wayward sister gets the royal treatment from their mother, while their better behavior yielded nothing. It's the last straw when the garage apartment they all want is thrown in, so they squat. Annie declares a war of attrition on them. Eric cowardly keeps out and hopes his sermon on the prodigal son may smooth things, but everyone feels targeted.

Robbie is happy with his new hot Latina girlfriend Joy Reyes and persuades her rich, devoutly Catholic father Ramon Reyes (for now) of his honorable intentions. The garage apartment squatters' resolve is self-sabotaged by their rivalry to get what shouldn't be Mary's and Ruthie's scheming. In the end return under the maternal yoke and make up (more or less forcibly) with Mary, who meanwhile repents, but Eric wisely doubts her sincerity and rectitude.

Robbie has spent too much time with Joy on top of his two jobs, so he demands a day off to study. She insists 'just this one day' and Eric convinces Robbie he should at least find out if it's a special day. On his way, he finds and picks up a stray dog tagged in Arizona. It turns out to be the pet who disappeared exactly two years ago with Joy's kid brother Joseph, and might now lead the police to the boy and his abductor. At home, the girls ask their parents to select ideal partners, leading to lots of speculation. Matt and Simon's attempt to pick up suitable girls by walking the twins backfires.

Simon's big day, the start of his driving lessons, finally arrived, but Eric just forgot about it. Grandpa Jackson seduces the knave into driving him around without a license, which leads through more bad grandfatherly advice to a televised police car chase. Jealous of Joy, Matt behaves childishly toward Robbie whose gentleman's attitude ultimately gives in. Lucy hoped Jeremy called to make up, but he just wants his engagement ring back. The local fire chief isn't fooled by Mary's eagerness to transfer.

Robbie volunteers his car to give Simon a driving lesson as Eric again fails to turn up as promised. Alas, they bump into Matt's car. Wilson has moved and left instructions not to tell Mary his new location. Firefighter Ben Kinkirk volunteers to pick up a rescue dog so he can visit Mary, who instantly calls him her true love again, but ends up found out. Meanwhile Lucy, who refuses to take off Jeremy's ring, is openly jealous of such a hunky suitor, Ruthie pretends not to care. Robbie's brother Ronald drops by and is furious to hear that his muse Lucy dated Robbie. Annie resigns her teaching post without consulting anyone.

While Robbie visits his mother in Florida, Ruthie sneaks in her friend Yasmine Halawi, a Muslim girl who has become the target of two bullies on the street. The whole family feels obligated to help the whole Halawi family, who has lived in Glenoak for years without problems, but every attempt proves difficult or even counterproductive; Matt and Simon nearly beat up the wrong suspects, and Ruthie's private school's board votes against admitting Yasmine.

Matt fails to warn Simon, who got Eric's permission behind Annie's back, about the dangers of attending older guys' parties. Simon's friend Morris drives him home but hesitates to ring the bell and see him safely inside his home; given spiked punch promises a killer hangover anyway. Meanwhile, Lucy settles her mutual good/popular-girl jealousy with Mary, but is nearly forced to drink at a get-together with coursemates.

The next Valentine's day, Robbie prepared a surprise for Joy. Mary meanly supposes the hotel she overheard him contacting by phone means another sex trap. Joy, who assumed the butler to be away like her father really is, isn't discouraged, but bitterly claims Robbie doesn't love her truly because he refuses to risk getting intimate. Matt contacts all his 'true lovers', wondering why he never stayed hooked up. Lucy again assumes Jeremy, who is back in town and double-dating with Mike, wants her back and pretends to have a date. Mary is shocked to see Wilson moved back and goes steady with her former school friend Corey Conway. Simon gets permission to let his hot senior date Maria 'help babysit' and gets her cute kid brother Jake to spare Ruthie dateless embarrassment.

Robbie's apparently firm happiness with Joy kindles envy in Matt, who is now so in love with wedding plans that he vows that his next steady date must be *the one*. Being commandeered into clinic duty, Matt misses his date with a promising candidate but he also meets a fellow med student, Sarah Glass, daughter of Rabbi Richard Glass. Sarah insists that they must meet each other's parents. Although both parental pairs plead against a mixed-religions marriage, the lovebirds soldier on.

Matt has married Rabbi Glass' daughter Sarah after one date. Robbie is mildly amused at the family's speculations and how they're worrying about whether Matt 'was dumber than Mary with Wilson'. Only Ruthie finds out, answering when Matt calls, but he swears her to secrecy. Meanwhile, Matt and Sarah go tell her parents first, but at the last moment she pretends they just got engaged, a lie they must now extend to the Camden home, where the 'news' only adds to the mounting stress.

Level-headed Robbie is the only one intentionally left home to babysit the twins when the Camdens accept a first dinner invitation at humorist Rabbi Glass's home. Mary beats Lucy to the punch faking illness so she can escape the event and try to seduce Robbie away from Joy. Simon takes his half-Jewish friend Morris along, but he fails miserably as a good example of someone from a mixed-faith household: he has no clue about the Sabbath or other Jewish traditions. Eric loses it completely when Matt says he's considering converting to Judaism, but they make up during a synagogue service.

Matt ignores at his peril Robbie and Simon's warning not to believe a girl's claim she needs no gift, especially concerning the diamond engagement ring. Eric's solution within budget, industrial imitation, is 'welcomed' even more bitter, until an heirloom is passed on. Lucy flew along to Buffalo with Mary to 'pick up her stuff', but discovers aboard she wants another shot at Ben. After provoking airport security, Lucy gets an instant crush on gallant, hot cop Kevin Kinkirk. She arranges a double-date with his brother, who turns out to be none other then Ben, who is however most suspicious of record-fickle Mary until Kevin gives the decisive push.

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.

Annie discovers Ruthie is writing to a Marine fighting in Afghanistan as part of a school project. The Camden family read what Ruthie has written to her pen pal about their lives and in turn learn about a Marine who so bravely has left his wife and son to fight in the war against terror. When Ruthie fails to get a response email at school and Eric hears about a helicopter going down killing two people he contacts the Colonel.

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.

The Camden family gather together for Matt and Sarah's wedding. Eric and the Rabbi make amends while Ben and Kevin decide to go to Glen Oak to pursue Mary and Lucy. Ruthie and Simon sort out their issues with Robbie.