Courtesy: Newport Aquarium

When Chloe Boyd, 11, and Cerri Okolica, 7, visited the Newport Aquarium in Newport, Ky., Sunday, they knew they would see fish, stingrays, sharks and maybe even an octopus.

The last thing they thought they would see was their soon-to-be stepdad, Navy Reservist Ryan Goodwin, who had been away from them and their mom, Goodwin's fiancée, Michelle Okolica, the past eight months on a deployment to Kuwait.

"It started out as a joke," Goodwin, 23, of Centerville, Ohio, told Goodmorningamerica.com of the surprise he wanted to give the girls because the deployment had been so hard on them, he said.

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"I said to Michelle, 'We could always take them to the aquarium and I could jump out with the sharks and say hi to them,'" he recalled. "From there it just took off into this big idea of being in the dive show and getting to talk to them from inside the tanks."

Chloe, for one, was so surprised that she only believed it was really Goodwin behind the scuba mask when he named the two shows the family watches together, "Futurama" and "My Little Pony."

"She got up and said that's definitely got to be Ryan," Goodwin said. "They loved it. Cerri said, 'I wish you had never been gone for that much days.'"

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Newport Aquarium says the military surprise between Goodwin, a Master-at-Arms ThirdClass in the Navy Reserve, and his fiancee's daughters was a first in the 11 years the aquarium has been hosting its dive shows.

"We've done a lot of marriage proposals and even did a wedding underwater one time, but this was so incredibly special," said Jennifer Meeks, the aquarium's dive safety officer. "We see these on TV all the time and we just felt so honored to have him [Goodwin]."

Goodwin emailed the aquarium with his idea and Meeks, whom Goodwin says was the brains behind it all, took it from there. Meeks said she knew they could throw Goodwin in with the sharks, literally, for this surprise because of his experience as a Navy diver.

"We were happy to host one of our own and help him out," she said. "He was thanking us profusely and we just wanted to thank him right back. There wasn't a dry eye in the house."

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Now that Goodwin is back home for the foreseeable future - he does not know when or where his reserve unit will deploy next - he plans to continue to pursue his teaching degree and plan for the family's next big milestone, one that will not be a surprise.

He and Okolica, 38, who have been dating for three years and engaged for nine months, plan to tie the knot on Aug. 10.

"That's going to be pretty hard," he said of topping what he called a "magical moment" for Chloe and Cerri. "I could probably show up to the wedding in camouflage and that would probably surprise Michelle as much as the girls were [surprised]."