Mandy Moore celebrates son Gus' third birthday.Photo:Taylor Hill/FilmMagic, Mandy Moore/Instagram

mandy moore son gus birthday

Taylor Hill/FilmMagic, Mandy Moore/Instagram

Mandy Mooreis celebrating her little guy’s big day!

On Tuesday, theThis Is Usactress, 39, shared a Reel onInstagramin honor of her son Gus' third birthday. Sharing photos of her son from throughout the past year, the toddler smiles, laughs and poses with his little brother Oscar “Ozzie,” 16 months.

“3! How in the world has time flown so fast? You amaze us in every way, Goosey,” the proud mom wrote in her caption.

“Your smile lights up every room, your curiosity about the world around you evolves daily, your obsession with construction vehicles continues to grow with a fervor, your tender heart and love for your family, including your brother (in between clocking him with a random toy of course) melts us…. We are so lucky.”

“Thank you for the greatest gift of being your mom. Cheers to more laughs, trucks and gummies, my sweet boy. We 💓 you!!! Happy Birthday!!” Moore concluded her post.

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In December, the mom of two shared with PEOPLE what shewas most looking forwardto during the holiday season.

“I’m excited for these next couple of weeks just to be home and cozy and enjoy this time of year,” Moore said at theDr. Deathseason 2 premiere in West Hollywood.

This season marked the first year that Moore and Goldsmith’s oldest son, Gus, really began to understand the festive season. As a result, the mom of two was seeing Christmas through her little one’s eyes.

“He’s loving being a big brother and he is loving the holidays,” Moore said. “Now, he’s aware of it in a way that he wasn’t until this year, like last year, he was just sort of starting to grasp Christmas trees, but now he understands the concept of Santa and all of that is it’s so much more exciting.”

Earlier that same month, Moore appeared onThe Tonight Show with Jimmy Fallonand revealed that although she’s well known for playingRapunzelin Disney’sTangled, her older sondoesn’t seem to care.

“He couldn’t have cared less,” she told hostJimmy Fallonof her son’s disinterest in the 2010 animated musical film.

“I have asked him several times. I’m like, ‘You’ve seenFrozennow — do you want to watchTangled?’ He’s like, ‘No,’ " Moore said, laughing. “Itmeans nothing to him!”

source: people.com