July 9, 2014 - The deadly incident happened Wednesday afternoon in the Shore Haven Beach area of Westfield, New York.
According to the Chautauqua County Sheriff's Office, 37 year old Christen Stefan of Bethel Park, a suburb of Pittsburgh, was at the beach with her nine year old son Tyler and another boy who went swimming.
Christen swam out to help the boys when the inner tube type float they were using was forced into deeper water by wind and waves.
As the three were climbing out onto a cliff, Tyler fell back into the lake.
Investigators say Christen vanished underwater while trying to help her son.
She was found, but later pronounced dead at Westfield Hospital.
Tyler was rescued by a good samaritan after he drifted about two hundred yards off shore.
He was taken to the Hospital for treatment of hypothermia.