Girl fights off mother to save her sister from being drowned after 2nd sibling killed, sheriff says: "Her courage is amazing"

A mother drowned one of her daughters in their South Carolina home and was trying to kill another child when the oldest daughter was awakened by screams and managed to save her sister, authorities said.

Jamie Bradley Brun, 37, was charged with murder and attempted murder after the attack early Friday in their home on St. Helena Island, Beaufort County Sheriff P.J. Tanner said at a news conference.

Brun has talked to investigators and Tanner called it a horrific crime, but told reporters he wouldn't say why Brun wanted to kill her children.