FORT PIERCE, FL — Known for their gentle manner and curious natures, it's not unusual for a manatee to swim up to take a closer look at a swimmer or play water tag with one another, weaving in and out a group of kayakers or canoers.

The Blais family of Florida, however, saw a more playful side of the big sea cow when they visited Fort Pierce Inlet Park on July 4. (Watch the video at the bottom of this story.)

Leesa Blais said her sons, Evan and Logan, were surfing when two manatees began swimming around them.

"I was kind of nervous at first because I thought they were sharks when they first came up," Evan Blais said.

When their dad, Brandon Blais, told the boys they were just harmless manatees, Evan and Logan said they just watched the manatees circle around while their dad filmed the encounter on his GoPro camera.

Being Florida natives, the boys are familiar with manatees, but Evan said they've never been this close to one before.

"It was so amazing," Evan said.

But then one of the manatees did something the family never expected. It stole Evan's surfboard away from him. The family can be heard in the background as the manatee, floating on its back, held the surfboard between its flippers for a minute before turning it back over to Evan.

Now the video has gone viral, and Leesa Blais said her sons, who are entering sixth grade, are on Cloud 9.

"They are so happy and so excited the video is making so many people smile," she said.

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