VIDEO: Sneak Peek - 'I Call Marriage' Episode of THIS IS US on NBC

On the next episode of THIS IS US on NBC titled "I Call Marriage," Toby throws a wrench in Kate's weight loss journey. Randall struggles to accept his father's deteriorating health. Miguel and Shelly break some devastating news to Jack and Rebecca, which makes them worry about their own relationship. Rebecca receives an amazing work opportunity. Kevin examines his romantic past. The episode airs Tuesday, January 31st on NBC. Get a sneak peek below!

About the show: Sometimes life will surprise you. Starring Mandy Moore ("A Walk to Remember"), Milo Ventimiglia ("Heroes," "Gilmore Girls") and Sterling K. Brown ("The People v. O.J. Simpson: AMERICAN CRIME Story"), this refreshingly honest and provocative series follows a unique ensemble. As their paths cross and their life stories intertwine in curious ways, we find that several of them share the same birthday, and so much more than anyone would expect. From the writer and directors of "Crazy, Stupid, Love." comes a smart, modern dramedy that will challenge your everyday presumptions about the people you think you know.

Chrissy Metz, Justin Hartley, Chris Sullivan, Susan Kelechi Watson and Ron Cephas Jones also star.