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The Olympic swimmer and fiancée Nicole Johnson welcomed their first child, son Boomer Robert Phelps, on May 5, which Phelps announced via Instagram. "Best feeling I have ever felt in my life!!!" the new dad wrote. "Nicole and Boomer both healthy!!!"
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DADDY & SON
"Boomer & I are missing this handsome stud this morning," writes Johnson, captioning an adorable photo of the Olympic swimmer and their son.
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Like father, like son! Boomer is loving pool time as he lounges on a float with mom Nicole.
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Boomer goes for the gold – and enjoys every minute of it – in a onesie fit for the son of an Olympian.
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Phelps celebrates his first Father's Day with Boomer – and Johnson is there to document the candid moment. "You're such an incredible daddy to Boomer already & you can already see in Boomer's eyes how much he loves you!!" she captions the pic. "I look forward to watching your relationship grow."
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PUMP UP THE PAMPERING
Boomer gears up for bath time as mom Nicole reveals that the newborn is "already loving the spa treatment."
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"Boomer and I got some extra laps in today!!" writes the doting dad on Instagram.
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The pint-sized style star poses for the camera in an adorable bandana and glasses-patterned onesie.
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Boomer ups the cute factor in his car seat, as he takes a nap with his plush toy and blankets.
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Phelps documents a cute moment with Boomer, as the newborn greets his fans on Instagram. "Boomer says what's up y'all!!!" the award-winning swimmer captions.
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So sweet! Phelps and Johnson clock in some cuddle time with their cutie.
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"He's just the best!!!" writes Phelps on Instagram. "I can't stop just looking at our awesome little guy!!"
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Boomer practices his selfie pose with dad as the pair enjoys the weekend together.
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He may not be focusing on the camera, but Boomer continues to be the center of attention in this family pic.
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Have you seen a more relaxed baby? Boomer is living the good life, lounging poolside.
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"The little man and I don't wanna get out [of] bed this morning!!" writes the Olympian, captioning a photo of himself with his son in bed.
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"So incredibly thankful for not only my lil family but everyone and everything that has helped to make this the most amazing year of my life!!" wrote the newly-minted Mrs. Phelps.
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Is there anything better than having a lazy day in with your loved ones? (Spoiler: there isn't.)
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Boomer can't help but show his excitement after getting a smooch from his mom.
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In case you had any doubt, Boomer is a proud member of the cool kids club.
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NO IFS, ANDS OR BUTTS
The pint-sized cutie lets it all hang out while getting cozy on a plush animal.
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BABY ON BOARD
All smiles here! A jersey-clad Boomer gears up for a football game with his parents.
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LIKE FATHER, LIKE SON
Phelps and Boomer rock similar expressions, poses and outfits on the tot's 6-month birthday.
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OH, CHRISTMAS TREE
The Olympic swimmer documents the trio's outing to purchase their very first Christmas tree as a family-of-three.
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BEARER OF GOOD NEWS
In what could only be described as one of Boomer's cutest pics ever, Michael, Nicole and their adorable son pose for pics on the couple's wedding day — where Boomer served as ring bearer.
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Looking adorable as ever, Boomer slips into his favorite boots for a fall-inspired photoshoot.
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MOM, DAD & BABY
The trio dress in their best for the 2016 Golden Goggles Awards.
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Boomer — decked out in his holiday gear — is ready to take on Christmas.
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Have you seen a cooler kid?
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TAKE A SEAT
Boomer gets silly while getting comfy on his monogrammed chair.
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The Olympic swimmer's son channels his inner crab after bath time.
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Boomer cuddles with mom as the two take flight.
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"My ninja outfit for the day!" reads the caption accompanying a snapshot of a smiling Boomer in a onesie.
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Boomer trades in his swimming trunks for a footballon Super Bowl Sunday.
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LITTLE MUSTACHE MAN
So dapper! Rocking a suit, Boomer tops off his look with a mustache pacifier.
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All that's missing is the bottle ... of milk, of course!
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BRUSH WITH FAME
"What do you guys think of the new style?" the tot asks — as if he even has to.
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"These moments are just amazing!! I love taking a little nap with daddy!!" Boomer says. We bet Daddy agrees.
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IT'S A SMASH
"Is it the weekend yet?" Boomer asks. He just gets us.