Following a health scare on Halloween, Walden decides to reprioritize his life with Alan's help.
When Walden asks Alan to sign a pre-nup, Alan gets offended and has second thoughts about getting married.
Alan and Walden have a meeting with an adoption social worker that hinges on them being convincing as a loving couple. Meanwhile, Lyndsey returns after 60 days in rehab.
Walden and Alan meet a birth mother who's considering them to adopt her baby.
Walden decides to foster a 6-year-old boy, but begins to doubt himself when they don't bond like he expected.
When Alan realizes Louis thinks he's cool, he starts breaking Walden's rules in order to stay that way.
Alan and Walden befriend three moms at a kids' gym, but things get complicated when Walden becomes attracted to one of them. Meanwhile, Alan goes out for a girls' night with a group of moms.
Walden and Alan are determined to convince Louis that Santa Claus is real.
Walden discovers how challenging it is to be intimate with women when his foster son, Louis, is in the house. Also, Herb asks Alan if he can go on a date with Lyndsey.
Alan takes it upon himself to help Walden keep Louis after the social worker discovers he and Walden are not really a gay couple.
Walden joins a group for adoptive fathers, and finds it to be a nice escape from Alan.
When Alan breaks up with their social worker to get back together with Lyndsey, Walden worries it will affect Louis' adoption.
Walden fears if he breaks up with Ms. McMartin, it will jeopardize his adoption of Louis. Also, Alan hesitates when Lyndsey asks him to move in with her.
After they sign their divorce papers, Walden offers Alan the gift of his choice, but when Alan chooses something selfish and impractical, it puts his relationship with Lyndsey on the line.
Charlie Harper is alive. Or is he?
The series finale recalls the life—and presumed death—of Charlie Harper.