Police Investigating Drowning Deaths of 2 Brothers, Ages 3 and 4, and Their Adult Sister at Georgia Lake

Authorities are investigating the deaths of three siblings who reportedly drowned at a Georgia lake.

The bodies of 22-year-old Raven Powell and her brothers, 4-year-old Mason and 3-year-old Sawyer, were found in Clarks Hill Lake in Lincolnton, Ga., Thursday night, WRDW-TV reports.

Investigators haven't ruled out foul play. All three of the Powell siblings died earlier Thursday, a coroner's investigation reportedly found.

Citing the Lincoln County Sheriff's Office, the TV station reports bystanders discovered the brothers' bodies in Clarks Hill Lake. Law enforcement used SONAR equipment to locate the body of their sister.

"They were our world. They mean everything to us," a cousin, Hannah Redfern, said, according to WRDW-TV.

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"Both boys were the happiest ever," she said of the brothers who loved water sports. "You never seen them without a smile on their face, unless they were hungry."

Redfern added, "I don't even want to come back to the lake again."

A GoFundMe campaign is now active to help the Powell family cover funeral costs.

WRDW reports the Georgia Department of Natural Resources and the Georgia Bureau of Investigation are assisting the sheriff's office with the investigation.