A first post-mortem examination of Bobbi Kristina Brown has found the 22-year-old daughter of Whitney Houston and Bobby Brown had "no significant injuries".
According to Sky News, The Fulton County Medical Examiner issued a statement confirming that the cause of death has not been established and further laboratory tests will have to be conducted.
The tests may take 'some weeks' and a death certificate will not be issued until all inquiries had been completed and reviewed.
"Interpretation of autopsy findings and other information will also be challenging," the medical examiner's office said.
"However, an autopsy could be helpful to address questions which may arise about the cause of her unresponsiveness and eventual death."
The medical examiner said the time that elapsed from when Ms Brown was found unresponsive until her death would "complicate" its effort to reconstruct events.
The incident was described as a "drowning" by police, and doctors said Brown had suffered irreversible brain damage.
The news comes as Bobbi Kristina's father, singer Bobby Brown issued his first personal statement since the tragic passing of his daughter.
He said: "Krissy was and is an angel. I am completely numb at this time. My family must find a way to live with her in spirit and honour her memory."
Kristen Foster, a representative for the Houston family said on Sunday (26 July): "She is finally at peace in the arms of God. We want to again thank everyone for their tremendous amount of love and support during these last few months."
Michelle Gordon, the mother of Bobbi Kristina's boyfriend Nick Gordon, said in a statement that the death of the 22-year-old had devastated her son and their family.
"Nick loved and cared for Krissi deeply, and he has suffered greatly each and every day they've been apart," she said.
"Nick and our family are in mourning, and we ask that you respect our privacy. Our thoughts and prayers are with both the Houston's and the Browns during this difficult time."
The 22-year-old was found unresponsive in a bathtub in her Atlanta home on 31 January. She spent six months in a medically induced coma and after unsuccessful efforts at rehabilitation, was transferred to hospice care.
A $10m civil lawsuit filed last month accused Nick Gordon of causing her life-threatening injuries and stealing from her bank account while she was in a coma.
"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. No charges have been filed in the case.
Meanwhile the final heartbreaking moments of Bobbi Kristina's life have been revealed.
According to the Daily Mail, members of her immediate family gathered around the 22-year-old's deathbed at the Peachtree Christian Hospice in Duluth, Georgia, with her father holding her hand.
A picture of her late mother was placed on the bedside table, and as Bobbi Kristina slipped away the family said "Hallelujah".
A celebration of her life is provisionally planned for Thursday in Atlanta, a week before being flown to New Jersey to be buried alongside her mother, singer Whitney Houston, who died in tragically similar circumstances.
Bobbi Kristina's funeral is likely to take place in August at Fairview Westfield Cemetery in Newark, New Jersey.
The funeral will only be finalised on completion of inquiries by the coroner and detectives.