Mandy Moore 'Wasn't Braced' for Rebecca's Fate on This Is Us : 'I Think It's Surprising'

This post contains spoilers from This Is Us.

Mandy Moore wasn't prepared for how Rebecca Pearson's journey would conclude.

On This Is Us, Moore's character Rebecca has been battling Alzheimer's disease. This fight will eventually reach its end, resulting in the eventual death of the Pearson family matriarch.

In an interview with Entertainment Weekly, Moore opened up about the challenge of coming to terms with this arc.

"I don't know if there is a way to brace anybody," said Moore, 38. "I wasn't braced for it. I wasn't ready. I had no idea what I was about to read or what we were all going to endeavor to do. I didn't know how [series creator] Dan [Fogelman] was going to flesh out the end."

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She continued, "I would encourage people to come in with an open mind, and I'm sure they know where this is heading, but I think it's surprising. I imagine that this is [a] very real way for some people to imagine the end of their life."

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Last week's episode of the NBC drama, "Family Meeting," saw Kevin (Justin Hartley) inform his brother Randall (Sterling K. Brown) that he needed to return home as Rebecca's health continued to deteriorate.

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Saying goodbye to the beloved character hasn't been easy for Moore. For her, Tuesday night's penultimate episode, "The Train," was tougher to shoot than the series finale.

"I well up thinking about it," she told the news outlet. "It was a lot. This episode is definitely a lot more to take in than the actual finale, in my estimation."

"It's going to be sad to say goodbye to this family and see these characters, but I think there's a lot more wrapped up in 'The Train,'" she added.

Gregg DeGuire/Getty Images Mandy Moore

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Recently, Brown raved about Moore's efforts as Rebecca in the show's sixth and final season. The 46-year-old actor even argued she deserves an Emmy.

"Man, that woman. Y'all know Mandy Moore is eight years younger than me and she plays my mama," he said in an Instagram video last month. "There's never a moment on set where I'm like, 'Mandy Moore's too young to play my mama.' No, she is my mama. And the beautifully subtle nuanced work and the portrayal of someone going through what her character's going through, it's just exquisite, man."

This Is Us airs Tuesdays at 9 p.m. ET on NBC, with its series finale slated to air on May 26.