Playing in the park with cute little Billie, handsome student Wilson West meets Mary and both get butterflies. Wilson's impeccable charm, doctor-pa and record pass even Eric's paranoid muster, but on Sunday he divulges that Billie is not kid brother but his own son. At the airport to pick up maternal grandpa Charles Jackson, Matt is smitten at first sight on a girl he later traces and learns is deaf Heather Cain. They date, but she flees the party after some youths make fun of her sign-language. Eric and the kids welcome grandpa's new 'significant friend' Ginger, but Annie irrationally rages against any suggestion a successor for her ma could be less then diabolic.

Wilson West tells Eric that Billy is his son, unplanned but not unwanted, whose teenage mother died giving birth to the angel, which his parents help him raise. Dating privileges are maintained 'for observation'. Michael Towner bravely owes up being the one who accidentally hit Mary when she dashed after Annie, who realizes she's the guilty one but only tells off Matt's overprotective vindictiveness. Sign language in a deaf-run restaurant helps Matt patch up with Heather. Jimmy Moon dumps Lucy on account of her endless hair wining. Charles Jackson nearly lost hope Annie would turn round and Ginger imposed 'a break', but both women come to their senses after some surprising 'counseling' and fibs. Mary is released home, but recovery up to basketball level is far from certain.

Eric suddenly decides to celebrate his and Annie's 19th anniversary with a vow-renewal ceremony to make up for their spartan wedding; meanwhile, murder-victim's widow Nora Chambers tells him she wants to meet her husband's unrepentant killer Martin; Wilson West has been trying to help Mary all summer, but she only gets ruder and refuses to try to walk without crutches; Simon worries that the attic won't be ready for him to move into before school starts; Matt fights jealousy over Heather's Canadian houseguest; Lucy agonizes over Jimmy Moon dating another girl.

Matt gets bad news from his girlfriend, and goes to Philadelphia; Mary calls it quits with Wilson; Ruthie learns a lesson about kissing at school.

Simon wants to buy the perfect gift for Deena; Lucy's ex-boyfriend is spending time at the Camden's home; Heather is engaged.

The whole Camden family is invited to Matt's deaf ex Heather's wedding to Mason, celebrated by Eric. Matt brings current girlfriend Shana, yet ends up convincing the bride to leave the groom at the altar and drive away together. Wile his ex Lucy flirts with Joe, Jordan gathers the courage to tell her he's dating Mary. Simon is confused after being kissed by Deenah's cahoot.

Matt brings unamused Heather, who hoped he would propose again, back to church, where he exposes after some hesitation groom Mason's flaw, while desperately trying not to lose 'abandoned' Shana. Simon learns the kiss was a 'love test', which is rewarded with more, and Jordan encourages to just enjoy it without excessive worries. Jordan tells Lucy, who out of mere jealousy makes out with wedding guest Joe. Eric has a hard time accepting Julie's sudden announcement to marry Dr. Hank Hastings, but doubts soon shake that couple to be.

New parishioners Carver's son Bobby has a condition, allegedly ADD, but former Tourette's-patient Louis Shea, MD recognizes that's the problem. Only pa Bill Carver can't cope with the diagnosis on account of the family past. Simon sticks up for Bobby against the bully jocks captain, while Mary is upset over an insensitive remark from Simon. Matt is in a stage where he refuses to take calls from Shana, the next bodes even more trouble for their long-distance relationship.

The parents insist on spoiling the kids' Valentine's day by celebrating the baby twins' birthday and demanding presents. Robbie gets permission afterward to drive Mary to the coffeehouse where his parents met. Matt puts off telling Shana his ex Heather transferred to his college, but Mary spills the beans. Simon's first passionate kiss caused a love-bite, which Deena meanly insists to return, causing disastrous discovery. Matt sees Robbie with 'his brother's date', sees through it but isn't believed that's cheating, until the romantic trip's hidden agenda is revealed.

Each one of the Camden kids has a relationship problem; Mary decides to skip college and get back together with Robbie; Simon is dumped; Matt is torn.

Simon learns the truth from Deena about why she broke up with him; Ruthie and Lucy try to reconcile with their exes; Matt gets back together with Heater.

Eric rightly predicts that the kids will only be more trouble in the new school year, yet Annie enrolls in a college course. Simon's only friend is Jim, who drags him along into minor vandalism as a gang initiation. Matt grudgingly admits that Heather left him at the altar; Lucy learns that Andrew Nayloss made an irreversible mistake in France (his father sent him to Europe to keep him far away from Lucy over the summer). Mary starts a minimum-wage job and gets a credit card and still doesn't see college in her future.

Robbie and Cheryl ask Eric to marry them because of her pregnancy. He smells a rat and learns just in time that she intended to trick Robbie, who is grateful to escape a loveless marriage and offers to stay away from Mary. Lonely Simon has joined punk Norton's schoolmates gang. Lucy, who is lightly butt-slapped, and the Camden parents, make huge scenes over inappropriate remarks from some of the knaves, treating Simon as if he 'hates women'. Matt tries to help both sides understand, but fails, yet a real incident shows Simon's truly good nature. Matt can go for Priscilla after hearing from Heather she's dating another already.

A month later, perfect house guest Robbie is getting popular with most Camdens, except Annie who childishly splits hairs about his domestic input, meant to help her but making her feel redundant, while Ginger takes care of grandpa. Matt is unwilling to stand by John when he meets the Carter parents and seeks refuge with Heather, whose boyfriend Thomas gets them off their backs by suggesting they're a sheets magnate family. Mary starts a round of panicking with a false rumor that Robbie is dating Lucy. Simon is flattered when Robbie asks his financial advice and starts copying him, even Matt follows suits walking around shirtless. Robbie finds a surprising job and the perfect thank you gift.

Eric threatens Robbie with eviction because he thinks he's keeping secrets about Mary. The house is abuzz with secrets and preparations for an elaborate surprise party for Eric's birthday. Johnny drops Mercy on the Camdens' doorstep after Frankie abandons them. Mike trusts Lucy enough to look after his mother for a day, during which the woman surprises her, both by speaking and by what she says.

Robbie wonders why Matt is suddenly so friendly, ignoring it's because Matt dates his ex Cheryl, who wants him to tell Robbie but doesn't push that, while Robbie spontaneously tells he studies a course with Heather, who needs his help. Simon feels a social outcast when nicknamed 'virgin Camden' because his mother assured Sasha's blabbermouth ma he's sexually inactive, but actually schoolgirls line up to date him. Viciously jealous, Annie meanly forces Eric to give up counseling Serena, yet denies that's her doing and sticks to her guns after Ruthie commends her as bitchy selfishness-model.

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.

Lucy thinks Kevin's partner is keeping secrets from him, such as she is trying to become a detective. Matt is having problems in his marriage. Martin learns that everyone thinks he is having sex with Cecilia.

Cecilia breaks up with Martin because she wants to be with Simon. Matt continues to run into a former girlfriend and is concerned about his marriage falling apart. Ruthie's foreign exchange student visits and is now living with the Camdens.

Annie and Eric are delighted with Matt and Sarah's surprise visit in time for Simon's wedding--and not just because they announce they're expecting. Simon is relieved that he and Rose aren't expecting, therefore marrying purely for love; but the next minute he gets cold feet, at which Lucy eagerly pokes. More visitors, like Matt's one-time bride-to-be Heather, stir further reminiscing and speculations; Rose's ex Umberto even asks Eric's permission to sabotage the wedding. The big day is full of surprises, including from Matt and Carlos.