S12, EP13 "Boompa Loved His Hookers"
Walden worries that ending things with Ms. McMartin will become an issue; when Lyndsey asks Alan to move in with her, he hesitates.
S12, EP12 "A Beer-Battered Rip-Off"
Walden worries that Louis' adoption will be impacted when Alan breaks up with their social worker in order to get back together with Lyndsey.
S12, EP11 "For Whom the Booty Calls"
When Walden joins a support group for adoptive fathers, he discovers that it is a nice getaway from Alan.
S12, EP10 "Here I Come, Pants!"
After the social worker discovers that Alan and Walden are not really a gay couple, Alan tries to help Walden keep Louis.
S12, EP9 "Bouncy, Bouncy, Bouncy, Lyndsey"
Walden discovers how difficult it is to be with women with Louis in the house; Herb asks Alan if he can take Lyndsey on a date.
S12, EP8 "Family, Bublé, Deep-Fried Turkey"
Alan and Walden are determined to convince Louis that Santa Claus is real.
S12, EP7 "Sex With an Animated Ed Asner"
Walden and Alan befriend three mothers, but things get complicated when Walden becomes attracted to one of them; Alan joins a group of moms on a girls night.
S12, EP6 "Alan Shot a Little Girl"
Alan decides to break Walden's rules so he can keep up an appearance of being cool in front of Louis.
S12, EP5 "Oontz Oontz Oontz"
Walden takes in a foster child named Louis but wonders if he made the right decision when they don't bond as he expected.
S12, EP4 "Thirty-Eight, Sixty-Two, Thirty-Eight"
A birth mother considers having Walden and Alan adopt her baby.
S12, EP3 "Glamping in a Yurt"
Alan and Walden must be perceived as a loving couple during a meeting with an adoption social worker; Lyndsey returns from rehab.
S12, EP2 "A Chic Bar in Ibiza"
Alan has second thoughts about getting married after he's asked to sign a pre-nup.
S12, EP1 "The Ol' Mexican Spinach"
After a health scare on Halloween, Walden decides he needs to change his life -- but needs Alan's help to do it.