Justin is in rehab and asks the family to join him for a group therapy session. Kitty visits Robert McCallister's at his home as she considers his job offer. Holly makes room for herself at Ojai, and Nora decides to join her.
To prove she and McCallister are not a couple, Kitty tries out a dating service. Kevin meets a guy who seems very interested in him, but claims he isn't gay. Sarah is struck by jealousy, and Tommy can't handle Julia's sex hormones.
It's Nora's birthday and her family is preparing an elaborate surprise party. Nora's mother shows up, and the kids' video greeting contains more than they bargained for, while Kevin continues his concealed relationship with Chad.
Valentine's Day has twists in store for the family: Kitty goes fundraising with Robert and finds out he wants to run for President, Kevin plays with Chad's feelings, but ends up with someone unexpected, and Justin gets a call from Tyler.
As Tommy thinks back to conversations with his father, he comes to a decision about his own future. Sarah's marriage is at a crossroads and she and Joe see a therapist. And Chad makes a move to make things right with Kevin.
News of William's and Holly's illegitimate daughter, Rebecca, shakes the Walker family to the core. Kevin causes an indirect coming-out for Chad, Justin breaks off with Tyler and a furious Holly declares war on Sarah and her family.
Nora invites Rebecca to a family dinner, and the family's problems with the new arrival are not well-concealed. Kitty partakes in a family dinner of her own when Robert's children come to town, and Chad invites Kevin to a film premiere.
Nora is so happy about her writing class that she decides to ask her teacher out. Kitty must go to Senator McCallister's home town on campaign work, and Sarah joins her for the weekend. Chad tells Kevin he finally wants to come out.
The Walkers decide to revisit an old tradition, game night with the Jones family. Kitty sets up a blind date between her brother Kevin and Jason McCallister, and several family members try to reach out to Rebecca as best they know how.
A kiss shared between Rebecca and Joe threatens his marriage. But does Sarah need to know? Nora goes on a date with her teacher, Mark. When a helicopter crash kills two of Robert's staff it causes strong reactions from him and Kitty alike.
It's time for the opening of Tommy and Holly's winery, but not everyone has celebrating with Holly at the top of their agenda. Nora takes the opportunity to invite Mark to join her, but ends up in a spirited fight at the party.
Julia gives birth prematurely, and when one of the twins has severe complications she and Tommy have a difficult choice to make. A former soldier tries to blackmail the Senator with information about his past. Joe moves out.
The family decides to throw an engagement party for Kitty against her wishes. Saul meets an old friend recently divorced from his wife. Justin spends time with his brothers and sisters before going to Iraq, but Nora refuses to say goodbye.
By the end of summer, Nora has not heard from Justin in Iraq for three weeks. Kitty takes a break from campaigning to be with her family, and they insist on taking her out on her birthday. Sarah has sex with Joe, but what does it mean?
Justin returns from Iraq, but with severe injuries. Nora wants to help him as much as she can, but that may be too much. Sarah asks Joe to move back home, but he has different plans. Kitty gets Robert in trouble at a radio talk show.
Kevin defends Scott in a DUI case; Justin continues to refuse medication; Julia decides to take her daughter and move back home to Arizona temporarily; Robert's ex-wife plans to tell all on the Larry King show.
Kitty and Nora take Sarah to a spa on her wedding anniversary. Justin is tempted to relieve his pain. Scotty sees Saul at a gay party and Kevin confronts his uncle. Tommy is desperate about Julia leaving and looks for comfort.
On the eve of Robert's televised debate appearance, Kitty finds out she is pregnant - and the rumor runs through the family. Sarah is shocked when Joe seeks primary custody of their children.
Kitty brings in an old acquaintance to help handle her pregnancy's impact on Robert's campaign. Rebecca discovers Justin's new drug habit. Paige doesn't respond well to her parents' new custody arrangement.
Rebecca reveals Justin's painkiller addiction to the family, and they stage an intervention. Robert is on the campaign trail, but is under pressure privately and professionally. Saul reveals a secret that astonishes his sister.
Kitty plans her wedding, but can't seem to make it feel like her own. Nora rediscovers her boyfriend from forty years ago, A business consultant uses his charm on Sarah, Julia returns to Tommy, and things happen between Kevin and Scotty.
The day of Kitty and Robert's wedding arrives amid fears that a damaging story will break about Robert's war record. Justin asks Lena to the wedding, and Tommy feels the pressure. Kevin brings Scotty, but Jason is still on his mind.