Mandy Moore Is 'Fully Channeling My Rebecca Pearson' as She Celebrates First Holiday Season with Her Family of 5 (Exclusive)

The 'This Is Us' alum partnered with Shutterfly to create her candid holiday card and personalized presents

Mandy Moore is gearing up for her most "dreamy" holiday season yet.

The This Is Us alum, 40, chatted with PEOPLE about her collaboration with Shutterfly as part of their new holiday card and gifting collection as she celebrates her first holiday season as a family of five.

The actress opens up about how meaningful it is to spend this time of year with her husband Taylor Goldsmith, sons August "Gus," 3, and Oscar "Ozzie," 23 months, and daughter Louise "Lou" Everett, 6 weeks, right by her side.

As a new mom of three, Moore tells PEOPLE, "I am fully channeling my Rebecca Pearson these days," referencing her beloved This Is Us character. "I don't know how she did it all, quite frankly."

Despite the "big three" chaos, Moore says, "We're soaking up this special moment. It just feels dreamy. Her brothers are doting and so loving and just beside themselves with how much they love her." She adds that "it's very, very sweet" to watch her babies grow so close together so quickly.

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Related: Mandy Moore Shares Her Family's Adorable Costumes as They Celebrate First Halloween with Baby Daughter Lou

"We're finding our rhythm and are just so excited about the upcoming holidays," she shares, adding, "It's my favorite time of year in general, and the fact that now we're kind of sliding right into Halloween then Thanksgiving then Christmas, it feels extra special to be able to do it all together as a family of five."

Moore and Goldsmith didn't make any big holiday plans this year. Instead, Moore says, "We're excited to hunker down at home and be all together."

"Our family is truly complete," she sweetly adds, so while they're cozied up at home, "We'll figure out some of the new traditions that we want to start and incorporate."

With a household full of toddlers and a newborn, Moore shares, "This partnership with Shutterfly truly couldn't come at a better time because it helped me get my ducks in a row and make sure that we got a picture in place so we can send out a holiday card."

She emphasizes how important holiday cards are to her as a mom, not only to "celebrate this for the first time as a family of five," but because, "one of my favorite things about the holidays is giving and receiving holiday cards."

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"Shutterfly makes it so easy to design, to get them sent off, to make it personalized, all of that," she tells PEOPLE. "Especially with how much is on our plate in particular at this given moment, It's just such a no-brainer. Again, this is something that I am most excited about during the holidays, so I'm glad we have it."

When it comes to getting that picture-perfect family photo, Moore says, "I'm a big fan of the candid shot." For her, the imperfect snaps hold "a sense of humor that makes people smile, or just remind me of this moment in time where we're still figuring out what's going on."

In addition to candid cards, Moore loves gifting friends and family "personalized gifts," such as Shutterfly's custom ornaments. "I'm not super sentimental about a lot," she admits, "but when something is personalized, it means so much."

Following her holiday card photo shoot, Moore plans to "use some of these pictures that we took and give these personalized ornaments for the holidays — and selfishly create that for ourselves too."

Personalized ornaments are actually a tradition for the family. "We have them from when Gus was a baby and from when Ozzie was a baby, and being able to celebrate their first Christmases and first holiday seasons is special," she explains.

With the perfectly imperfect holiday card, photo-filled gifts and a complete family of five just hanging out together in their home, Moore raves, "I think the holidays are going to be even more meaningful this year."