By Andrea Lucia

ENNIS (CBSDFW.COM) – An Ennis family says the Texas Department of State Health Services is investigating after their 2-year-old was exposed to a dangerous strain of E.coli.

Landon Huston is now on life support at Children’s Medical Center Dallas.

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“He’s usually up, rambunctious, running around,” said his mother, Lindsey Montgomery. “I’m ready for my little boy to be back.”

The family took a trip to Oklahoma two weeks ago, cooling down in a hotel pool and at a natural spring.

“I’d never heard of people swimming and get E.coli,” said his father, John Huston.

Landon’s mother described his symptoms.

“Three, four days later, Landon’s got fever, diarrhea, really sick,” said Montgomery.

But by the time a test confirmed E.coli, his kidneys were shutting down. Montgomery said the CDC interviewed her trying to determine the source of the infection.

“They asked me where he had been, what food he had ate, any restaurants,” she said.

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Dr. Jeffrey Kahn, Children’s Health Chief of Pediatric Infections Diseases, said it’s normal for a case like this to trigger a public health investigation.

“That suggests that there’s some contamination somewhere. It’s usually water or food and typically that means it’s not just one individual who’s been exposed,” he said.

Just when Landon’s parents thought the worst was over, he suffered a complication while undergoing dialysis.

“They, of course, rushed us out of the room and into the emergency room. He lost like a Coke can’s full of blood. But they were amazing. They were able to do the surgery in like 30 minutes,” said Montgomery.

Landon’s parents said he is expected to fully recover, but they will never take his good health for granted again.

“You think it’s not gonna happen to you,” said Montgomery. “Stuff does happen.”

Kahn said the only way to determine the source of an E.coli infection is by finding others who are sick and tracing patients to the same food or water source.

The Oklahoma State Department of Health told CBS11 it had not had similar reports.

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Family members have set up a GoFundMe account to help cover medical costs and lost income –