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 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.

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.

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.