Michael Phelps Is a Dad -- See the Cute Announcement For His Baby Boy!

The Olympic swimmer shared the exciting news via Instagram.

Michael Phelps is officially a dad!

The 30-year-old Olympic gold medalist took to Instagram on Saturday to announce that he and his fiancée, Nicole Johnson, welcomed their first child, a baby boy.

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"Welcome Boomer Robert Phelps into the world!!!" the champion swimmer captioned a black-and-white photo of himself holding his newborn. "Born 5-5-2016 at 7:21 pm !!! Healthy and happy!!!"

"Best feeling I have ever felt in my life!!!" he added. "@nicole.m.johnson and Boomer both healthy!!!"

The happy couple announced they were expecting back in November with an adorable photo of themselves holding a pair of baby swim Speedos. Leading up to the arrival of their little bundle of joy, Johnson, also 30, updated their fans with snaps of her growing belly.

"#BabyP will be here in no time!!" the Miss California USA 2010 beauty queen wrote via Instagram at 36 weeks along.

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She followed it up with a post of her "sister/bff," Ellice Boone, rubbing her baby bump while the two were relaxing pool side.

In more baby news, Blac Chyna and Rob Kardashian announced that they are expecting their first child together on Friday. This will be the first child for Kardashian, and the second for Chyna, who shares a 3-year-old son, King Cairo, with Tyga.