Mandy Moore Reveals Which This Is Us Storyline Made Her Cry the Most

As it turns out, the cast was reaching for the tissues on the set of This Is Us along with the rest of us.

Mandy Moore, who played matriarch Rebecca Pearson on the hit NBC drama, recently opened up about the storyline that made her cry the most, and her answer was both poignant and emotional. 

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"Oh my God, that's so hard to like distill down," Moore, who also stars in the upcoming season of Doctor Death, revealed to NBC Insider. Throughout its six-season run, This Is Us tackled so many issues and character journeys, from race to death to alcoholism. But there was one that was especially difficult for the singer and actor. "Anything towards the end with any of the Alzheimer's storyline was just like... it was hard to escape how emotional that was," she said.

Alzheimer's on This Is Us

Rebecca was diagnosed with early-onset Alzheimer's during the show's fourth season. The series consulted with USC's Hollywood, Health & Society program to create an informed and accurate depiction of the disease's progression, and according to research quoted in AARP, the storyline may have helped reduce stigma around talking about Alzheimer's, and many caregivers felt seen by Randall (Sterling K. Brown) and Kevin's (Justin Hartley) differing views on how to best care for their mother.

Alzheimer's also ties into the series' final twist: in the second-to-last episode, viewers met Marcus Brooks (Luke Forbes), who as a child survived a deadly car crash on the same night that beloved Pearson dad Jack (Milo Ventimiglia) died. Years later, Brooks goes on to make pioneering breakthroughs in the treatment of Alzheimer's, even after Rebecca has died of the disease.

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In an interview with People, show creator Dan Fogelman explained why he introduced Marcus' storyline. "I always thought that this second to last episode, in a way that hopefully surprises, would tell the story of another person, potentially a child, who had survived in that same moment that Jack had been lost," Fogelman explained. "It's very much at the center of the show."

He continued, "So, on the very night that the beloved patriarch of the family died, [Jack] passed on advice that translated to a whole other family he'd barely know, for the family of a child who was saved that night. It felt important to us to have that story inside this very episode."

Reporting by Stephanie Gomulka