Milo complains that Grandparents Day is coming up at school and doesn't feel Henry is interesting enough to participate. Lena and the kids urge Martin to reconnect with his long-estranged father, Brock, to rebuild their relationship. Meanwhile, Lisa continues to struggle financially and considers moving back home with her parents. Elsewhere, after listening to a true crime podcast, Maya worries that Frank has a dark past he has been hiding.
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.