Celebrity Parents Mandy Moore Shares Lullaby Created for Baby Gus as Husband Taylor Goldsmith Celebrates Her Birthday Mandy Moore and husband Taylor Goldsmith welcomed their first child, son August "Gus" Harrison, on Feb. 20 By Nicholas Rice Nicholas Rice Instagram Twitter Associate Editor, PEOPLE People Editorial Guidelines Published on April 10, 2021 12:30 PM Share Tweet Pin Email Photo: Vivien Killilea/Getty Images Mandy Moore and her husband Taylor Goldsmith are one musical family! The This Is Us actress, who turned 37 on Saturday, shared a clip on Instagram of the Dawes singer, 35, performing a lullaby that the couple crafted for their infant son, August "Gus" Harrison. Set to the tune of "Desperado" by the Eagles, Goldsmith sits at the piano as he sings about bedtime for the pair's baby boy. "August Goldsmith, I think it's time you tried sleeping/ If there's something you're needing, we'll be in the next room/ And if you're dreaming, oh dream it, dream of mommy and daddy/ Cause it's way more than likely we'll be dreaming of you," Goldsmith sings on the track. "@taylordawesgoldsmith and I have been singing this song to our little guy since he was a 🥜 in my 🤰," Moore wrote alongside the clip. "Side note- you have the best dad, Gus. 💓💓💓." Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. On Saturday, Goldsmith celebrated his wife's birthday with a sweet tribute and photo of the mother-son pair. "It's this Supermom's birthday today. The nucleus of the family. The one who knows exactly what she wants our future to look like and then makes it a reality. The one who is mothering a 7 week old, is back working again, and somehow still makes each of her animals feel individually loved and looked after," the musician wrote. "Love becomes a bigger word every day I'm in your orbit. I love you more than I know how to say. Happy Birthday @mandymooremm," the dad of one shared. Mandy Moore Says Son Gus Loves Baths 'Just Like His Mama' Alongside Sweet Snap of Newborn Moore and Goldsmith welcomed their first child on Feb. 20. Moore announced the arrival of her son with a sweet Instagram post. "Gus is here 💙💙💙💙," she wrote in her caption. "Our sweet boy, August Harrison Goldsmith." "He was punctual and arrived right on his due date, much to the delight of his parents," the mom of one added. "We were prepared to fall in love in all sorts of brand new ways, but it goes beyond anything we could have ever imagined." Goldsmith similarly shared the same photo and caption as his wife when he announced the arrival of his son on his Instagram account a few days later. RELATED VIDEO: Mandy Moore Recalls 'Harrowing' Birth of Newborn Son Gus: My Plans 'Went Out the Window' Earlier this week, Moore shared an adorable snapshot to Instagram of her 6-week-old son happily enjoying what the This Is Us star said is one of her favorite at-home activities — a bath. In the photo, Gus is all smiles with his body submerged in the water as Goldsmith sweetly looks on while keeping his son afloat with his hand. "He may be @taylordawesgoldsmith's twin but he sure does love a bath, just like his mama. #thisisgus," Moore captioned the post. 37 Incredible Mandy Moore Throwback Photos in Honor of Her 37th Birthday Many of Moore's famous friends dropped some comments about baby Gus on her post. Costar Chrissy Metz wrote, "Get out of town with this cuteness!!!!!!," while Parker Bates, who plays a young Kevin Pearson on the hit NBC series, said, "He's so cute!!" Amanda Kloots also commented, writing, "omg so cute," while fellow new mom Ashley Tisdale wrote, "I spy @_willababy_," in reference to the baby bathtub that Gus was photographed in.