It happened at Sims Bayou at about 10:30am Sunday. According to Houston police, family members were there on an outing.
Police say Ricardo Guidel, 9, and Diana Morales, 5, and another relative, age 12, were fishing and swimming in the bayou when Ricardo and the other boy began drowning. As Laurencio Guidel, 31, who was fishing with the kids, attempted to rescue them, Morales fell in the water and also began drowning.
"It can get deep in certain areas, but very marshy. So you can start sinking where you thought you were at one height and it's very difficult to pull yourself out," said Capt. Ruy Lozano with the Houston Fire Department.
A bystander found the kids, pulled them out and started CPR on them. They were then transported to Memorial Hermann Hospital, where they were pronounced dead.
Police say the 12-year-old boy was able to get out and is doing OK.
Laurencio's body was recovered a short time later by the HPD Dive Team. The investigation is continuing.
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