Whitney Houston's daughter Bobbi Kristina was rushed to hospital Sunday suffering from stress, a day after the death of her pop star mother, reports and a family friend said.

"She was taken to hospital and treated for stress," the friend told AFP, speaking on condition of anonymity after media reports that the 18-year-old was taken to the Cedars Sinai hospital in Beverly Hills.

Bobbi Kristina is Houston's daughter from her stormy 15-year marriage to singer Bobby Brown. She was taken by ambulance from the Beverly Hilton hotel, where Houston was found dead on Saturday, reports said.

The TMZ celebrity news website reported that various prescription pills were found in Houston's hotel room, quoting family members as saying she used Xanax, which is often used to treat anxiety.