Kevin and Scotty make a commitment to be life partners, Saul finally deals with his identity in a public way, and the family discovers that William (guest starring Tom Skerritt) kept yet another painful secret from his family. Guest starring are Tom Skerritt as William Walker, Luke MacFarlane as Scotty Wandell, Michael Adler as Doug Manning, Michael O’Keefe as Wally Wandell, Jayne Brook as Bertha Wandell and Parvesh Cheena as Jordan. "Prior Commitments” was written by Greg Berlanti, Monica Owusu-Breen and Alison Schapker and directed by Ken Olin.