Easton Whipple was pronounced dead just after 10:30pm Saturday by a doctor at Brazosport Memorial Hospital, according to the Brazoria County Sheriff's Office.
About an hour and half earlier, the toddler and his family were at a Lake Jackson home in the 100 block of Pesimmon, visiting his grandparents.
Whipple's mother said children were coming in and out of the house and someone must have left door unlocked. Soon, the mother noticed her son was missing.
After a 15-minute search for him, the family called 911. That's when emergency personnel found his body in a pond behind the grandparents' home.
CPR was started immediately and continued for 20 minutes at the hospital before a time of death was declared.
The boy's body has been sent to the Galveston County Medical Examiner's Office for an autopsy.
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