Criminal Minds star A.J. Cook has welcomed her second son with her husband Nathan Andersen, her rep confirms exclusively to Us Weekly. Credit: Donato Sardella/Getty Images for InStyle Magazine

Baby's on her mind! Criminal Minds actress A.J. Cook has welcomed her second son with her husband, Nathan Andersen, her rep confirms exclusively to Us Weekly.

Cook, 37, gave birth to their baby boy, Phoenix Sky Andersen, on Thursday, July 23, at 5:49 a.m., the rep tells Us. Little Phoenix weighed in at 7 pounds, 6 ounces, and measured 20.5 inches.

The star and her husband are also proud parents to a 6-year-old son, Mekhai Allan. The family's newest addition nearly overlaps birthdays with mom, who celebrated her 37th on Tuesday, July 22.

Her husband shared a photo via Instagram of their celebration. "Took Alexander [A.J.] out for a fancy birthday meal," he joked, alongside a pic of his wife's bump nestled up against a bag from In-N-Out.

Took Alexander out for a fancy birthday meal. @ajcook @ajcookofficial

A photo posted by Nathan Andersen (@nathanandy) on Jul 22, 2015 at 2:19pm PDT

Cook announced her pregnancy this past March via Instagram. "Miracles do happen and don't believe anyone who tells you otherwise," she wrote, alongside a photo of her growing tummy. "#Blessed #Bump."

Her equally excited spouse confirmed the news via social media, revealing the baby's gender that same day. "Since @ajcook announced we are expecting a new addition to the clan, I guess it's my responsibility to inform everyone it's a boy!" Andersen wrote.

Cook's last social media update was nearly two weeks ago on the Fourth of July. "'MERICA!!!!!!" she wrote, alongside a funny beachside snap of her husband adorned in flag shorts and her growing baby bump while she held a Coke in a koozie. "Happy 4th! @nathanandy."

'MERICA!!!!!!???????????????? Happy 4th! @nathanandy

A photo posted by @ajcook on Jul 4, 2015 at 10:48pm PDT

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