Boy Dad Michael Phelps Reveals Whether He and Wife Nicole Will Try for a Girl: 'We Got Everything'

Michael Phelps and his wife Nicole Phelps are happy being a family of six.

When asked in a recent interview with E! News whether or not he and Nicole plan on trying for a girl after having four boys, the 28-time Olympic medalist said he thinks “that's it” when it comes to having more kids.

“Nicole will tell you too,” he said. “I think she said she wanted a girl for me, but we have Onyx.”

Onyx is the family's Great Dane, which they adopted in March. "Onyx is our girl, so we got everything," Phelps, 39, said. "We got four boys [and] we got an awesome girl now."

Phelps first posted a photo of Onyx on Instagram back in March. At the time, he captioned the snap, “Our sweet baby girl…. Onyx 🖤."

Phelps recently partnered with Purina Pro Plan and starred in the docuseries Fueled By, which showed how athletes use Purina Pro Plan to keep their pups healthy and active. 

Phelps told PEOPLE in a July 1 interview that Onyx “fuels me to be able to be the best me. And I think that competitiveness I'll never lose."

“She's somebody that can sense my feelings and emotions and understand when I'm having a good or bad day," he continued. “It's the simple things like her just coming and giving me love — just nudging me. It's her telling me she's there to support and help me. Those small things mean so much." 

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Phelps and Nicole share  four boys together — Boomer, 8, Beckett, 6, Maverick, 4, and Nico, 5 months — and he spoke with E! News about how important fatherhood is to him.

“Fatherhood has been something that's been special just because [of] growing up kind of without a dad,” Phelps said. “Being able to kind of always be around and see every single step has been a treat."

Phelps also revealed that he's committed to his physical and emotional health, which is something he wants to pass on to his sons.

"Three boys — 8, 6, and 4 — kind of get roughhousing and get into it — there are a lot of big emotions," he explained. "So when they're going at each other, we pull them apart and you say, 'Lion breath.' And then they're able to talk through the things that they're experiencing in their stomach."

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The Olympian added, “As a dad, that's really cool to see. We're giving them a tool to be able to help them control their emotions and identify their emotions and I think that's something that I didn't learn until later in life. "

“So some of those little small things are hopefully going to make an impact and change how they look at mental health in the future."