Mandy Moore and husband Taylor Goldsmith welcomed their first child, son August Harrison on Feb. 20

Mandy Moore is loving being a mom!

Just days after announcing that she and husband Taylor Goldsmith had welcomed their first child together, son August Harrison, the This Is Us actress, 36, shared an adorable new photo of their baby boy.  

"One week earthside," Moore wrote alongside an image that showed her newborn looking cozy underneath a blanket, going on to share that it's been "the best week ever."

Ending on a humorous note, the singer included a hashtag referencing both her hit NBC show as well as her son: "This Is Gus."

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Although Moore's birth plan had to be altered, her baby boy arrived right on time. 

"Gus is here 💙💙💙💙," she wrote on Tuesday, while announcing her bundle of joy's arrival.  

"He was punctual and arrived right on his due date, much to the delight of his parents," Moore 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."

Mandy Moore pregnancy
Mandy Moore and Taylor Goldsmith
| Credit: Jenna Jones

The star went on to reveal the sweet story behind her son's name, which Moore said she and her husband decided on early into their pregnancy.  

"It was last August when @taylordawesgoldsmith and I found out we were having a boy (it's also Taylor's birth month) and we always loved the name," she wrote days later alongside a photo of the newborn sleeping with a small grey blanket with his name embroidered across it.

Moore also shared that her son's blanket holds even more sentimental value for the couple.  

"For our anniversary in November, T gifted me with this blanket with the 'A' (for Amanda) made from extra material from my wedding dress and 'T' (for Taylor) from his wedding shirt," she wrote. "Felt like a very fitting amalgamation of our whole story. I can't wait to pass this on to our sweet August one day. 💙💙💙💙."

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Moore, who announced she was expecting last September, has been open about her difficult first trimester and fertility struggles. In a January interview with Romper, she said she was "very hesitant" to believe she was pregnant because of past issues with her uterus.

As for what the future may hold, Moore recently shared that she's open to the idea of adding to her family.  

"We're not at the end of the rollercoaster ride yet, and like, I'll do this again," she said during a recent appearance on the Informed Pregnancy Podcast. "I'm so ready to do this again. Even if I was as sick as I was during the first trimester, there is something I think in the third trimester that is so profoundly magical and beautiful."