New mom Mandy Moore shares the sweet origins of her baby boy's name

On Tuesday, Mandy Moore and husband Taylor Goldsmith announced the birth of their first child — a baby boy named August, or Gus for short. In her latest Instagram post on Wednesday, the "This is Us" star revealed that the name was largely the result of some beautiful timing.

Not only did the couple find out that they were having a boy last August, but Goldsmith — a singer and guitarist in the California rock band Dawes — also was born during the fateful month.

"We always loved the name ... so it was settled very early on in our book," Moore shared in the caption.

The name's origin story accompanies a photo of a baby blanket, featuring "August" spelled out onto it. Moore explained that the blanket was an anniversary present from Goldsmith, with whom she celebrated two years of marriage last November.

"(Taylor) 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," Moore 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."

Related: It's a boy for the "This Is Us" star and her musician hubby.

While August's arrival marks the beginning of motherhood for Moore, her acting career has helped her understand what this next chapter will look like. On "This is Us," for example, she portrays a woman with three kids.

“It’s funny, I mean having played a sort of matriarch of a family for the last five years and getting to sort of see children at various different chapters and stages, I feel like I’m as pseudo-prepared as I can be,” Moore told TODAY's Hoda Kotb in November. “I’ve had babies and toddlers and I have adult children, so I’ve kind of gotten a pretty good taste and lay of the land.”

Still, Moore's first Instagram post of August expressed that motherhood has already exceeded all of her expectations.

"We were prepared to fall in love in all sorts of brand new ways," she wrote. "But it goes beyond anything we could have ever imagined."

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