Megan Fox and Brian Austin Green welcome a son

It's a boy for Megan Fox and Brian Austin Green!

The tight-lipped twosome, who didn't even confirm they were expecting until June, welcomed their first child together on September 27. They named their bouncing baby boy Noah Shannon Green.

[Related: Megan Fox confirms pregnancy with bump-baring bikini photo]

After keeping their baby news under wraps for more than two weeks, the "Transformers" actress gushed about her new addition on Facebook earlier today. Describing the baby as "healthy, happy, and perfect," Fox went on to write, "We are humbled to have the opportunity to call ourselves the parents of this beautiful soul and I am forever grateful to God for allowing me to know this kind of boundless, immaculate love."

The happy new parents certainly come armed with parenting experience. Green, 39, has a 10-year-old son with his ex-girlfriend Vanessa Marcil, and Fox, 26, is often seen out in Los Angeles with her stepson, who was the only witness at the couple's 2010 Hawaiian wedding.

Fox has been very candid about her desire to have children with Green, who is best known for his role in "Beverly Hills, 90210," but appeared in Charlie Sheen's "Anger Management" over the summer. "I want at least two, probably three [kids]," she told Cosmopolitan earlier this year. "I've always been maternal." As for her relationship with Green, who is 12 years her senior, she told the magazine: "I truly feel like he's my soul mate. I don't want to sound corny or cliche, but I do believe we are destined to live this part of our lives together."

[Related: Megan Fox makes scantily clad cameo in 'This Is 40′]

Now in nesting mode with baby Noah, Fox has a little time off before she has to head back to work. Her next film "This Is 40," which is touted as a "Knocked Up" sequel, will be released in December.

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