An autopsy will be needed to evaluate what led to the death of Bobbi Kristina Brown, authorities have said.

In a statement on Monday morning, the day after her death, the Fulton County Medical Examiner’s Office said the time that elapsed from when she was found unresponsive on January 31 until her death on Sunday will “complicate” its effort to reconstruct events.

Bobbi Kristina, daughter of Whitney Houston and Bobby Brown, died on Sunday at Peachtree Christian Hospice in Duluth, Georgia, about six months after she was found face-down and unresponsive in a bathtub in her suburban Atlanta townhome. A police report described it as a drowning.

Bobbi Kristina Brown with her late mum Whitney Houston
Bobbi Kristina Brown is the daughter of the late Whitney Houston and Bobby Brown (Dan Steinberg/AP)

“Interpretation of autopsy findings and other information will also be challenging,” the medical examiner’s office said in the statement. “However, an autopsy could be helpful to address questions which may arise about the cause of her unresponsiveness and eventual death.”

Bobbi Kristina had been hospitalised for months in Atlanta — eventually being placed in hospice care — after being found in a manner grimly similar to the way her megastar mother died three years earlier.

Nick Gordon, who shared her home with her, said at the time it seemed Bobbi Kristina wasn’t breathing and lacked a pulse before help arrived.

Nick Gordon with Bobbi Kristina Brown in 2012
Nick Gordon found Bobbi Kristina in January (Jimi Celeste/AP)

“The Roswell Police Department continues its investigation into the circumstances preceding and surrounding the time of the original incident leading to her death,” the medical examiner said in Monday morning’s statement.

The medical examiner did not release a timeframe for the post mortem, but said additional lab testing might take several weeks.