Mae Whitman gives birth to first child

Mae Whitman has given birth to her first child.

The Parenthood actress named her son after co-star and good friend, Miles Heizer.

Mae, 36, took to Instagram to share the news with a quip about stealing the new-baby limelight from Justin and Hailey Bieber, who also recently became first-time parents.

"Not to be a Bieber about it but I too just gave birth to our son, Miles," Mae wrote. "From the moment we heard the first tiny sound out of his tiny piggy mouth we were besotted."

Mae added her son was "the kindest, gentlest, smartest, funniest little beebee," and revealed the newborn was named after her Parenthood co-star Miles Heizer.

"He's our best friend (pretty much exactly like his namesake Uncle Miles)," Mae wrote. "We are infinitely grateful he chose us as his parents."

Miles played Mae's younger brother in the TV drama.

Mae also took time to express her appreciation of the medical team at Huntington Hospital in Pasadena, thanking them "for guiding our little family through all the unexpected twists and turns safely and with love and grace".

While her partner is unknown, Mae also thanked "everyone in our circle who has shown us such radical generosity and support".