Mandy Moore is celebrating her son August "Gus" Goldsmith on his first birthday.
The This Is Us actress, 37, took to Instagram on Sunday, Feb. 20, to commemorate her first child's special day by posting an adorable video tribute filled with some of the toddler's cutest moments thus far.
Set to the tune of Randy Newman's "Memo to My Son," the montage sees Gus wearing a pair of sunglasses and trying to play the piano with his musician dad Taylor Goldsmith. It also features an image of Mandy breastfeeding the toddler while still sporting her TV character Rebecca's aged-up makeup look.
"Gus- Being your mom is a gift beyond my comprehension, a love so fierce and mighty that I know I will never touch the depths of," the actress captioned her post. "Happy Birthday to our ever joyful and curious boy!!! You turned on all the lights, Goosey." She also added the hashtag #ThisIsGus.
Dancing With the Stars contestant Amanda Kloots, Claire Holt and Ashley Tisdale all joined in the birthday festivities in the post's comment section, with Ashley writing, "Happy birthday gus!!!!"
Mandy and her husband welcomed their son less than three years after they officially tied the knot in November 2018.
Taking to her Instagram Story Feb. 19, the day before the child's birthday, the actress reflected on her experience going into labor and meeting her son for the very first time.
"One year ago today, I went into labor and looking back at my doula @ccmeyer's incredible photos capturing it," she wrote. "I'm feeling all of the feels right now."
"It's so funny how a year later, pictures take me right back," she shared. "I can't touch the pain anymore but I remember the magnitude of it. Cracked wide open in the biggest and best way possible."
For her final photo, Mandy included an image of her gleefully smiling while holding her newborn son. "The greatest moment of my life, along with every moment since," she wrote. "We love you to the moon, Goosey!!"