By CBSBoston.com Staff

BOSTON (CBS) – As 8-year-old Christian DeJesus sat in the emergency room at Children’s Hospital Wednesday night, he and his dad talked about the boy’s scary lesson.

“They’re children and they do things unexpectedly,” said the boy’s father, Jose DeJesus. “But now he understands not to jump in the pool.”

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Indeed, his dad says Christian wandered into the deep end at the DCR pool on Turtle Pond Parkway in Hyde Park Wednesday afternoon – despite being a weak swimmer – and went under.

Christian DeJesus (Image credit Jose DeJesus)

“I just lost another child two months ago to leukemia,” says the elder DeJesus. “So, I wanted to jump into action and save my son.”

DeJesus says he was pulling the semi-conscious boy from the water as a female lifeguard scrambled over and immediately began rescue breathing on the little boy at poolside.

“She did a fantastic job,” says State Police Lt. James Bazzanotti. “She went right to her training and communicated well. She talked to the child – who was not breathing well and still gurgling. She did a great job – fantastic.”

By the time the youngster was brought to Children’s Hospital he was conscious and alert. But doctors held him for several hours anyway – just as a precaution.

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“I prayed,” says his father. “I was praying for the best for him. But I knew he was in good hands.”

On his cell phone, Jose DeJesus showed us a picture of his son and daughter in the shallow end of the pool — taken just moments before the incident.

But as Christian sat in the ER, unaware of how close he came to tragedy – his dad acknowledged a debt to the young lifeguard.

“I don’t know her name, but I will thank her when I go back there,” DeJesus says.

He believes his family will likely return to the swimming pool – but promises his kids will be on a shorter leash.

“Life vests,” he says firmly. “For sure.”

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The DCR closed the pool right after the incident but says it will re-open Thursday morning, when temperatures are expected to soar into the mid-90’s.

CBSBoston.com Staff