The 32-year-old retired Olympic swimmer shared a first photo of son Beckett Richard on Tuesday after wife Nicole Phelps gave birth to the infant Monday, Feb. 12.
"Magical moments yesterday... Nicole and I would like to introduce Beckett Richard Phelps to the world!" Phelps captioned a picture on Instagram of Nicole with Beckett and their 21-month-old son, Boomer Robert.
"We had a healthy baby boy and a healthy mama. I truly do feel like the happiest man in the world," he gushed. "Being able to build our family to now 4 (6 with doggies) is so incredible! #familyof4now."
Nicole shared a similar photo and a sweet message on her own account.
"Our family grew by one yesterday," she wrote. "Meet Beckett Richard Phelps. I'm surrounded by boys and I couldn't be happier."
Phelps and Nicole welcomed Beckett just one day after being feted by family and friends at a baby shower.
The couple posted photos from the party on Instagram, but had yet to announce their baby's sex.
"Such an amazing day celebrating our #babyshark!!" Nicole wrote. "We are so thankful for everyone who was able to be with us and everyone who was with us in spirit."
Phelps and Nicole married in June 2016, shortly before the swimmer announced his second retirement. Phelps remains the most-decorated Olympian of all time with a total of 28 medals, 23 of which are gold.
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