Report: Bobbi Kristina Brown used drugs before being found in tub

Bobbi Kristina Brown, the daughter of Whitney Houston, was high on drugs the morning she was found face-down and unresponsive in a bathtub, People magazine reported.

The magazine quoted a source "familiar with the details of the situation" who said Brown was under the influence on Jan. 31, the day she was discovered in a bathtub at her Georgia home. Multiple people said the 21-year-old is a heavy drinker and frequently uses heroin, cocaine and Xanax, People said.

Brown has been on life support since the incident, which happened just days before the third anniversary of her mother's death. Brown is the only child of Houston and singer Bobby Brown.

The magazine cited another source as saying Bobbi Kristina Brown has been "in and out" of rehab over the last three years and said the aspiring singer was "distraught" as the anniversary approached.

"How thin she had gotten is an indicator," the source said. "This girl was trying hard, but she didn't have any support system. She was still dealing with a lot of grief over her mother."

A police investigation is ongoing and few details on Brown's condition have been released. Her family has said Brown is "fighting for her life" at Emory University Hospital in Atlanta.

The Associated Press reported Thursday that doctors had replaced Brown's breathing tube with a tube usually used for patients who need to be on a ventilator for an extended period, according to a person close to the family.

On Feb. 11, 2012, Houston was found face-down and unresponsive in about a foot of water in a bathtub in the Beverly Hilton hotel, just before the Grammys. She later died, and authorities concluded she had accidentally drowned.

Investigators found a dozen prescription-drug bottles in the hotel suite and listed heart disease and cocaine use as contributing factors in Houston's death.