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Rossdale first announced the birth of their son on Twitter saying, "Welcome Apollo Bowie Flynn Rossdale 2/28/14," Saturday confirming the little bundle of joy was born on Friday. He also added that Bowie and Flynn are the maiden names of each parent's mothers. 

Apollo joins his family of now five, with big brothers Kingston, 7, and Zuma, 5. Rossdale, the frontman of Bush is also the father of model Daisy Lowe, 24, from a prior relationship.

The No Doubt singer wasn't too public about her pregnancy news, but she did reveal her baby's gender in an Instagram and recently posted another picture to from her baby shower. 

It looks like Stefani will still be the queen in her house for a while, and she'll definitely have her hands tied with three growing boys. We can't help but say welcome to baby Apollo.

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