MEMPHIS, Tenn. (AP) — Authorities say two more children have died of their injuries in a house fire that had killed one other child and two women in Tennessee.

Media reports say 13-year-old Christyon Johnson and his 12-year-old brother, Charles Johnson III, died at a Memphis hospital over the weekend.

Authorities say their 43-year-old mother, Patrice Graham, 66-year-old grandmother, Patricia Baker, and their 4-year-old nephew, Travis Murrell Jr., also died in Thursday's fire.

Pyketa Graham is the sister of Christyon and Charles Johnson. She says the boys were "sweet and funny. They made friends easily and loved basketball."

The cause of the fire remains under investigation.