LOS ANGELES COUNTY (KRON/CNN) — A family in Southern California is warning others parents Thursday night after their son had a bad reaction after swimming in a popular lake.

Fifteen-month-old Parker Nguyen’s father had no idea that last Sunday’s trip to Pyramid Lake near Castaic in Los Angeles County could make the boy sick.

But that is just what the family believes after swimming in the water there.

Nguyen is on video talking about algae on Parker’s swim shirt.

Jenny Nguyen brought her GoPro camera into the lake to video her son, and when she put it underwater, she saw this…algae floating past the lens. 

Fifteen minutes later, there was a medical emergency.

Parker was covered in welts, his lips were blue, and he was having trouble breathing.

His frantic parents called 911.

“From the sheriff and the lifeguard and the staff at the lake, they knew what it was,” Family attorney Alexander Napolin said. “They suspected it was the blue-green algae, and the toxin, and they said they wouldn’t never allow their children to swim in the lake.”

Parker has a peanut allergy.

At first, his mom and dad thought he might have eaten something but they quickly ruled that out.

What the Nguyen’s didn’t know was that the area had been closed to swimming 10 days earlier because of a blue-green algae bloom.

The warning was downgraded in mid-July.

Officials from the state department of water resources say signs are up at the park entrance and on the lifeguard tower cautioning people about toxic algae in the lake.

The Nguyen’s claim they never saw any signs about the algae.

“They would not have been in that water,” Napolin said. “They want the public to know so that other parents and children aren’t affected. This could have been fatal.”

Parker’s parents gave him Benadryl before he was rushed to an emergency room which they think saved him.

A UC Irvine expert on blue-green algae says that a person swimming in it could get a skin irritation.

That would be the most common reaction if there was a problem.

While the state says signs are up, the Nguyen’s insist they were in the water with other families and no one ever warned them.WHAT OTHERS ARE CLICKING ON:

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