Mae Whitman Announces Birth of First Baby With Adorable Photo

Mae Whitman is officially a mom!

The Good Girls and Arrested Development alum surprised fans with the joyful news that she welcomed her first baby in a sweet post she shared to her Instagram grid on Wednesday, Aug. 28.

Alongside a photo of the newborn's foot, the 36-year-old actress shared that she had recently given birth to a son, who she named Miles in an apparent nod to her friendship with actor Miles Heizer, who played her on-screen brother (Drew Holt) in Parenthood, the NBC drama that ran for six seasons.

"Not to be a Bieber about it but I too just gave birth to our son, Miles," she began in the caption, joking about how she copied the pose in the photo fellow new parents Justin and Hailey Bieber shared when they announced the birth of their son late last week.

"From the moment we heard the first tiny sound out of his tiny piggy mouth we were besotted. He is the kindest, gentlest, smartest, funniest little beebee and he’s our best friend (pretty much exactly like his namesake Uncle Miles @younggoth)," Whitman, who first revealed she was pregnant this past May with a photo featuring Heizer and co-star Lauren Graham, gushed.

Though she has not spoken about her relationship status or identity of the baby’s father, she said, "We are infinitely grateful he chose us as his parents."

The Below the Belt producer also added a special shout-out to those who supported her and her growing family during this incredibly exciting time.

"Thank you to @kaiserbente and @carynfields and everyone at @moxiebirth and @huntingtonhospital for guiding our little family through all the unexpected twists and turns safely and with love and grace and to everyone in our circle who has shown us such radical generosity and support," she wrote. "We love you! We’re so happy!♌️ 👶🏼🦁."

Whitman's post was soon overwhelmed with celebratory comments from fans and fellow Hollywood stars like "Uncle Miles," who was so touched, he only left an "🥹" emoji.

"Just perfect," added Christina Hendricks. "So much love."

Martina McBride also shared her elation, writing, "Sooooo happy for you! Cant wait to meet him. ❤️."

"Welcome to the world Miles!" exclaimed actress AnnaSophia Robb. "Congratulations Mama!!!"

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