The star gave birth to her bundle of joy and posted the good news on social media on Tuesday.
WATCH: Hints that Meghan Markle was expecting another baby
"Gus is here," she wrote. "Our sweet boy, August Harrison Goldsmith. He was punctual and arrived right on his due date, much to the delight of his parents.
"We were prepared to fall in love in all sorts of brand new ways, but it goes beyond anything we could have ever imagined. M + T."
Mandy and her husband, Taylor Goldsmith, didn't give details of how they chose the name but their baby comes just days after the British royal also welcomed her first child.
Mandy shared a sweet photo of her child
Eugenie and husband, Jack Brooksbank, named their son, August Philip Hawke.
But Mandy's connection to the royals doesn't end there! She adopted another baby moniker from them too, because his middle name of Harrison is the same as Prince Harry and Meghan's son, Archie.
Mandy has been excitedly sharing updates on her pregnancy
Mandy and Taylor will raise their son in LA too, where they own a beautiful house on a hilltop in Pasadena.
The plush pad has sweeping views and a lush, green garden, with large trees to offer shade from the hot sun - and plenty of space to raise a baby!
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