Pregnant Shawn Johnson Opens Up About Baby No. 3 and 'Chasing' Around Her Two Toddlers (Exclusive)

The Olympic gold medalist — who is already mom to kids Jett and Drew — is currently pregnant with her third baby with husband Andrew East

Shawn Johnson East couldn't be happier to soon welcome her third baby.

The retired Olympic gymnast, 31, recently announced that she was pregnant by posting a series of photos on her Instagram that revealed the exciting news. While speaking with PEOPLE about her partnership with Dairy Queen for the brand's Miracle Treat Day campaign, Johnson East also opened up about her baby on the way and how life has been with her two kids.

"[I] was just feeling off and took a pregnancy test," Johnson East tells PEOPLE of finding out the news. "It was really nothing romantic or crazy like a YouTube video. And [I] told my husband literally three minutes later."

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Related: Shawn Johnson Is Pregnant! Former Olympic Gymnast and Husband Andrew East Expecting Third Baby

"We were just sitting on the couch watching TV and I had done calculations and it was right around my father-in-law ['s birthday] who we lost last December. It took me off guard and I was like, 'Babe, guess what? I'm pregnant. And it could be on dad's birthday, which is wild.'"

Although she was low-key about telling her husband the big news, Johnson East says that her former football player husband Andrew East, 31, is "very excited" about welcoming their newest addition.

"He loves babies. He's a phenomenal daddy and he is very excited," she tells PEOPLE. "I'm definitely the more anxious one, just hoping everything goes smoothly."

Luckily, this pregnancy has been relatively easy for Johnson East, who says that she has "pretty easy pregnancies."

"I was very nauseous in the first trimester, which is normal. I think the only difference is I'm just more tired chasing around two toddlers while being pregnant."

She tells PEOPLE that her two kids — son Jett James, 2, and daughter Drew, 3½ — are looking forward to becoming older siblings. "I don't think Jett understands," she says. "Maybe he does, but Drew is very, very excited and she talks about it daily or kisses my belly daily or something. It's adorable."

As for what she's most excited about after her baby arrives, Johnson East says that she can't wait to introduce "the baby to my other babies. I think they will be the greatest and it'll just be exciting to have that moment where we can share it all together."

The future mom-of-three is supporting Dairy Queen's Miracle Treat Day Campaign, which benefits Children's Miracle Network Hospitals. Johnson East tells PEOPLE that the campaign is incredibly important to her as it helps raise critical funds for the hospital. "I feel like it's the least I can do just as a human," Johnson East says of her partnership.

"Especially as a mom these days, I feel like I know first-hand, God forbid we ever need these resources, I would want them to be there. And doing a campaign like this...being able to raise money is amazing."

On July 27th, fans are invited to head to their local Dairy Queen to purchase a Blizzard treat, where one dollar or more will be donated to Children's Miracle Network Hospitals. "It sounds silly almost to say because it's so easy and it benefits so many people and so many beautiful children and families to help provide funds for their treatments," Johnson East says.

While her pregnancy announcement may have taken the cake for the most exciting news this summer, the gymnast still has had plenty to celebrate, including son Jett's 2nd birthday this past month. "We had a pool party. We sang, we did presents," she tells PEOPLE, sharing that they celebrated his birthday a few days early.

"So technically his birthday in his mind was yesterday," Johnson East says. "He doesn't understand dates yet, which is great. But yeah, we just had some friends come over with their babies, we swam, had snow cones, opened a couple of presents and celebrated him."

The family of four has also recently been able to fly with Andrew as their pilot. "Yeah, anytime," Johnson East says of letting her kids fly with her husband again. "I trust my husband, he's a phenomenal pilot and our babies really get a kick out of it and they're great travelers."

"They're great travelers on the little planes, on the big planes, commercial or daddy flying," she tells PEOPLE. "It's a lot of fun though. It's really special for them."

"We have a little flight simulator at home where [my husband] practices and our son loves it. He'll wake up in the morning and be like, 'Daddy fly? Daddy fly?' And he'll do it with him. It's cute."

Johnson East is due in December, which happens to be right in between two major holidays — Thanksgiving and Christmas. "I feel like when you get into the whole trying to get pregnant world, you have ideal times to get pregnant, but very quickly learn that it's not easy and you just pray that you can get pregnant," she says. "So for us, December will be amazing."

"We'll get to share it, have this baby around the holidays and it'll be wonderful."

For more on Johnson East's pregnancy, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here.

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Read the original article on People.