Mandy Moore announces birth of son 'right on his due date'

Mandy Moore is officially a mum!

The 36-year-old This Is Us star announced the birth of her first child, a son named August Harrison Goldsmith, on her Instagram on Tuesday.

"Gus is here," Moore wrote in the post along with a photo. "He was punctual and arrived right on his due date much to the delight of his parents."

She added that they were prepared to, "Fall in love in all sorts of brand new ways, but it goes beyond anything we could have ever imagined."

Several of Moore's celebrity friends congratulated her on the happy news.

"Congratulations on your sweet beautiful new love!!!!!! Little Gus," the O.C. star Rachel Bilson wrote.

Alison Brie commented, "Congratulations!! Sweet little Gus! Much love to the whole family!"

Meanwhile, Claire Holt wrote, "Ohhhh my goodness!!! Congrats love! So happy for you guys."

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Moore announced her pregnancy last September, with her husband, Taylor Goldsmith.

"Baby Boy Goldsmith coming early 2021," she captioned the post.

In a recent interview with Romper, the singer said she was "very hesitant" in the early stages of her pregnancy.

"I sort of was holding my breath until 12 weeks," she said at the time. "The little things kind of get me. Like, I was online buying pacifiers yesterday and I just turned to my husband and I was like, It's real. There's going to be a little human that needs a pacifier."

This is the first child for Moore and Goldsmith, a musician she married in 2018.