Olympian Michael Phelps and his wife, Nicole (née Johnson) Phelps, are expecting a second child together and shared the news Tuesday with several happy posts to fans on Instagram.

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“Lil mans going to be a Big Brother!!!” Nicole wrote. She was all smiles wearing shorts and a black tee and holding her son, Boomer, who had the positive pregnancy test in his hand.

>> See the post here

Lil mans going to be a Big Brother!!!

A post shared by Nicole Michele Phelps (@mrs.nicolephelps) on Aug 29, 2017 at 9:28am PDT

The proud papa shared the same image of his little family on his own Instagram account, writing, “Number 2 on the way!!!! So excited!! Wonder if it’s a boy or a girl??”

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Boomer Phelps posted a tribute to his little brother or sister on Instagram to his 795,000 fans with a image of the pregnancy test and a big smile on his face.

“So excited to see what mama is having!! Do I get to have a brother or a sister?!?” his parents wrote in the caption.

>> See the post here

So excited to see what mama is having!! Do I get to have a brother or a sister?!?

A post shared by boomer phelps (@boomerrphelps) on Aug 29, 2017 at 9:27am PDT

Boomer Phelps stole the hearts of Americans as he cheered his father on from the stands during the 2016 Olympic Games in Rio. Nicole and Michael Phelps wed in a top-secret ceremony in June 2016, had a public wedding the following October and threw a bash with family and friends to celebrate their union on New Year’s Eve 2016.