A schoolgirl was stabbed to death in her own bed by an intruder who also tried to murder her mother, authorities said.

Lainie Williams, 17, was killed in the attack at her home in Cefn Fforest, South Wales, on Thursday morning while her mom, Rhian Stephens, 38, was severely wounded, according to the British news outlet Wales Online .

The teen’s 8-year-old brother hid under his bed after hearing his older sister’s screams, the Sun said .

Cameron Cheng, 18, was charged Saturday with Lainie’s murder and the attempted murder of Stephens, BBC News reported .

He was also charged with possession of a bladed instrument in a public place and will appear in court in Newport on Monday, according to reports.

Cops went to the family’s home at around 7:15 a.m. Thursday after reports that t

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