A newly divorced couple embrace the unconventional as they co-parent their children by trading residences each week, alternating between one living in the main house and the other in the garage apartment as they also adjust to being single for the first time in years. This new arrangement will land Lena and Martin in some precarious situations, with Lena’s doting sensibilities and Type-A personality clashing with Martin’s laid-back temperament as they attempt to raise the kids separately but together. What will Lena and Martin do with their unfamiliar moments of freedom? And how will they manage their feelings when this freedom is met with the nostalgia for what they once shared as a couple and their mutual longing for their family to be whole again? With the help of friends Arthur and Camille, plus Lena’s sister, Maya, this former couple will explore what it means to live apart...under the same roof.
Lena and Martin were once madly in love. But, like many marriages, time and circumstance eventually took their toll, and they decide that everyone's lives would be better if they got a divorce. Facing a daunting real estate market, the couple decide not to sell their house and to "Bird Nest" instead. The 'on-duty' parent will live in the house while the 'off-duty' parent will live in the detached garage. As Lena begins to dip her toes into the dating waters, Martin begins to see his own culpability in his marriage falling apart.
Afraid that the answer could ruin his chances with Lena, Martin finds every way he can to avoid asking Lisa Apple if she is pregnant, while the potential pregnancy makes Lena more and more distant. At the same time, Lena worries Mason is changing himself to please his new girlfriend and finds parallels to her own relationship with Martin. Elsewhere, Maya tells Frank a pretend story about her "friend" who is dating someone new and pregnant to gauge what his honest reaction will be.
Lena decides to call Martin's bluff on selling the house but is surprised when he actually begins making necessary repairs to get the house ready to be sold. The realtor sends over a contractor to deal with the structural issues she discovered in the house. Meanwhile, upset that Mae is not enjoying her sophomore year of high school, Lena invites Emma-Rebecca, Mae's friend from camp, to visit; yet she seemingly brings a trail of bizarre and supernatural events along with her.
Lena and Martin’s escalating battle for control of the house is put on hold when Milo announces he wants to go to a school for the gifted – to which they think he will not be accepted. Meanwhile, they both meet a contractor for the house, Vlad, but Lena undermines him and scares Vlad away. Things get uglier between Lena and Oliver after she introduces a new member to the family as payback for all the back-and-forth about the house. Elsewhere, Lena and Martin give conflicting advice to Mason on how to deal with his recent breakup.
After breaking the news to friends and family about the divorce, Lena has to deal with her son Mason's growing pains; Martin secretly tries to atone for an oversight and surprise his ex-wife.
With this being Martin's week in the house to take care of the kids, he discovers that daughter Mae finds his parenting skills to be lacking and a bit sexist. Meanwhile, Lena's time in the garage gives her time to contemplate going out with a handsome doctor and perhaps taking the relationship to the next level.
While Lena gets ready to go out on a first date with a handsome man whose sexual chemistry is undeniable, Martin finishes his dance lessons with Charlotte and attempts to try to fix things with Lena on what would have been their 16th wedding anniversary. Meanwhile, Mason is being teased by his friends for not being as sexually active as they claim to be; and to prove that she would be a good mom, Maya attempts to watch over Lena and Martin's kids, with questionable results.
Lena goes out on another date with Wes, whom she's smitten with; but unbeknownst to her, Martin is doing his best to take care of a sick Milo. Meanwhile, Maya makes a decision on whether or not to become a single mother.
Unbeknownst to Lena and to her dismay, Martin starts to date a familiar face and surprisingly begins to see the world of relationships through brand-new eyes. Meanwhile, Lena tries to show she's a good role model to her kids by proving a point and faking a night out on the town.
Martin and Lena are thrilled when they hear that Mae has won the lead in the school musical but are surprised to learn that she has been confiding in the school psychiatrist, Dr. Rydacto, about her feelings toward how not divorced they are acting. Meanwhile, Martin has reservations about how fast his relationship with his girlfriend is going and asks Mason for girl advice.
Despite Lena and Martin getting along as co-parents, they must determine the best way to orchestrate Milo's upcoming birthday festivities based on their new system of boundaries. Meanwhile, Oliver is pleasantly surprised when Jenna shares a birthday invite with an unforeseen guest. Elsewhere, Maya takes matters into her own hands and reveals a surprise guest of her own.
Lena and Martin choose to share the house for the summer while the children are away at camp despite Lena's reservations, but soon realize it might not be the worst idea. They collectively agree to throw their annual backyard pina colada party where they will celebrate their independence from their children. Elsewhere, a friendly face returns back home and Martin can't help but see it as