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49th NAACP Image Awards - Arrivals

WhileThis Is Ushas been busy changing our lives and making us weep, it’s been doing the same for its cast members.

“[The show] has changed my life in every way,”Mandy Mooretells says in PEOPLE’s special edition,The Complete Guide to This Is Us.“It’s given me purpose.”

“I think the ending will be very satisfying for people,” Moore said onJimmy Kimmel Liveafter telling host Jimmy Kimmel that creator Dan Fogelman told her how the hit NBC series will conclude.

Though she couldn’t go into any more detail than that, Moore did speak to PEOPLE about the upcoming season, which premieres Sept. 25 on NBC.

In the wake of the loss of Jack, “we see the kids are just about to go off to college,” Moore shares.

RELATED VIDEO: Mandy Moore Feels ‘Protected’ With ‘This Is Us’ Co-Star Milo Ventimiglia

“I’m looking forward to watching [Rebecca] sort of reconcile how she’s going to be able to step up to the plate,” she says. “I think she really just regards Jack as the golden parent and the superhero, so I’m curious to see what life is like as a single mom, and be a parent to these kids after this tragedy.”

Playing Rebecca has given Moore the opportunity to “grow and stretch as a human and as an actor” in ways she hadn’t expected, but was hoping for.

Ron Batzdorff/NBC

This Is Us - Season 2

“I have an outlet for what’s in my heart, what’s in my mind,” she says. “I have an outlet for all of that now because of the show.”

Find out what’s next for the Pearson family in PEOPLE’s new special issue,The Complete Guide to This Is Us, which includes new interviews with the cast and creators and exclusive photos.Available on Amazonand wherever magazines are sold.

This Is Usseason 3 kicks off on Sept. 25 on NBC. If you need to catch up, season 2 will be availableon DVDon Sept. 11.

source: people.com