This season picks up a year after the events of the previous season finale revealing what has happened since the events of "On The Road Again" such as whether Robert and Holly survived the car crash and how Saul is dealing with life after discovering he is HIV positive.
The Walkers attend a swanky launch party for Luc's underwear advertising campaign where 14-year-old Paige falls in with the wrong crowd; despite several visits from Justin, Holly still struggles to remember the things that were once most important to her; Kevin is saddled with a runaway juvenile delinquent; and just as Nora very publicly admits that she's taken a part-time job as a florist ,she's approached by a radio show producer with a job offer.
Kitty continues her stay in Ojai, trying to reinvent herself, when she meets a handsomely rugged handyman, Jack. As Kitty fakes her persona to seem like a local, she winds up in a situation that proves that honesty usually is the best policy. Meanwhile, the rest of the Walkers are in on a little surprise birthday celebration for Sarah; what they all don't know is that Sarah has been lying to Luc about her age to appear younger...
Justin and Rebecca reach an impasse in their relationship; Holly has a breakdown over her inability to remember her own daughter; Sarah struggles to keep up with the Joneses when Cooper lands the lead role in "Romeo & Juliet"; Saul takes a huge risk to make a romantic connection with a dear friend; and Kitty struggles with an affair of the heart.
Nora's motherly skills and advice catch the attention of a radio producer who invites her to audition for a new show. But when Nora follows through with the invite, she suddenly finds herself out of her league, competing with a famous personality, Dr. Alexandra Kirby. Meanwhile, as Kevin and Justin go through some life lessons of their own, Kitty heads back into the dating game with her Ojai handyman, Jack.
Everyone in the Walker family is willing to forgive and forget Scotty's infidelity. But when the family all put their best foot forward to help them reunite, things end up in a fist fight. Meanwhile Jack is reinvigorated by being back in the city and starts to pursue new ventures, but Kitty can't seem to picture herself in this new life, and Sarah and Luc share some exciting news with the family.
Justin suddenly takes a much more keen interest in Holly's recovery after a nurse at the hospital catches his eye; Nora's fellow radio host, psychiatrist Dr. Karl, finds his way into Nora's heart when he helps Sarah and Kitty resolve some old sisterly squabbles; and Paige helps Kevin and Scotty find forgiveness.
The charms and well intended matchmaking antics of Luc's visiting mother, Gabriela, quickly turn to high drama as she sticks her nose in Nora's romantic affairs.
Both Kitty and Nora very reluctantly make new romantic connections in unexpected places, Kevin's nerves about the adoption drive him to a disastrous bout of overindulgence, and Sarah's plans to spend one last romantic night alone with Luc go horribly awry.
With the holiday season come panic and discord in the Walker family when Nora takes a last minute getaway with Karl. Saul has a chance encounter with a past love, guest starring Richard Chamberlain as Stephen, who he believes had a lasting and very permanent effect on his life.
A scandal like no other hits the Walker family which causes Kitty to over-think her future.
In this 99th episode the family looks back to the events who made them who they are now. Tommy returns with surprising news, while his siblings all have to make very difficult choices. Kitty needs a break from her Life.
The Walkers are excited when Tommy comes down for a visit, but his new girlfriend's enthusiasm for Walker family history rubs the family the wrong way.
The Walkers' plans to celebrate Valentine's Day go horribly wrong when Tommy tells Sarah about another secret that Nora has kept buried since they were kids, and Saul's hopes for a romantic evening with Jonathan are dashed by a visiting high profile food critic.
Though Nora tries her best to keep Brody at bay, she can't help but feel the long lost connection between them, and Justin reaches out to a homeless vet reluctant to accept help getting back on his feet.
Nora and Sarah fly out to Washington DC to "surprise" Evan for his birthday, but what they're really after is the truth behind Kitty's extended trip to the east coast. Meanwhile, Kevin and Scotty are thrilled to have officially signed the papers to be Olivia's parents, but the excitement quickly fades when Olivia seems a little nervous about moving in and starting a new life.
When Olivia's brother shows up and sets out to gain custody of her from Kevin and Scotty, the Walkers struggle amongst themselves to determine what's best for Olivia.
Emotions are running high in the Walker family when Nora and Saul find out their mother, Ida, has passed away.
Nora finally gives in to her feelings for Brody, which leads to a spontaneous romantic getaway. Meanwhile Sarah and Luc closely consider growing their family, and a chance encounter with Michelle raises Scotty's suspicions about her whereabouts for the past several months.
Parenthood is questionable for more than one member of the Walker family, as Justin keeps a closely guarded secret about the true paternal identity of one of his siblings and Scotty makes a shocking discovery that will bring a new life into the Walker family fold.
After Sarah confronts Brody about his being her father, she decides she no longer wants him to be a part of her life or Nora's, but Nora just can't seem to let him go. Meanwhile, Olivia struggles with the new addition of baby Daniel to the family.
As Sarah and Luc's nuptials approach, plans go horribly awry and the Walkers learn several surprising lessons about the real meaning of family.