The cast of NBC’s "This is Us" breaks down the 17th episode of the show in a web extra "That was Us."

The 17th after show features cast members Mandy Moore (Rebecca) and Milo Ventimiglia (Jack). The pair discuss show themes such as tough goodbyes and celebrating a full life.

"This is Us" is a drama that follows an extended family and the unique life struggles they each face. It airs Tuesdays at 9 p.m. on WBIR. Watch full episodes on NBC.com.