SIOUX FALLS - The mother of a man who died in an icy South Dakota river while trying to save a 6-year-old boy says she thinks of her son as "the biggest hero."

A search boat on Saturday discovered the body of 28-year-old Lyle Francis Eagletail in the Big Sioux River in Sioux Falls.

Eagletail and 16-year-old Madison Leigh Wallace died when they sought to save Madison's brother, 6-year-old Garrett Martin Wallace.

Margaret Eagletail tells KSFY-TV that her son sacrificed himself for Garrett Wallace, who emerged from the river and was uninjured.

The city of Sioux Falls is named after the Big Sioux River's cascading waterfalls in Falls Park, a tourist attraction where people often picnic or pose for wedding photos.

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