After she was found unconscious in her bathtub, the 22-year-old spent months in the hospital. She was later moved to a hospice and never regained consciousness.
Kristen Foster said she passed away on Sunday surrounded by her family and was “finally at peace in the arms of God”.
Brown was discovered face down and unresponsive in a bathtub on 31 January and placed in a medically induced coma. She never regained consciousness.
She was moved to a hospice in the city of Duluth, Georgia, a month ago after her condition deteriorated.
Brown was the only daughter of Houston and R&B singer Bobby Brown.
Houston was found dead in a hotel bath in Los Angeles in 2012.
The family posted a photo of Houston with Bobbi Kristina as a baby on whitneyhouston.com with the following message:
“It is hard to say goodbye. On Sunday, July 26, Bobbi Kristina Brown made her transition peacefully. The family thanks everyone for their loving thoughts and prayers. As Bobbi Kristina would say: ‘The wind is behind me and the sun is in my face.'”
“Bobbi Kristina Brown passed away July 26 2015, surrounded by her family,” Ms Foster added.
“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.”
She had spent the last months in two Atlanta hospitals, a medical rehab facility and a hospice, much of the time in an induced coma and on life support.
Her Houston family relatives announced last month that she had been transferred to hospice, a move usually reserved for end-of-life care.
“Despite the great medical care at numerous facilities, Bobbi Kristina Brown’s condition has continued to deteriorate,” said a statement signed by Pat Houston, Bobbi Kristina’s aunt, the executor of Whitney’s estate.
“As of today, she has been moved into hospice care. We thank everyone for their support and prayers. She is in God’s hands now.”
By the afternoon of June 25, police, and media cars and vans were seen parked outside the hospice as her family, including father Bobby Brown and Pat Houston, gathered by her bedside.
Her death, coming three years after her mother’s eerily similar demise, marks a double tragedy, one of the most heartbreaking of the celebrity world.
She was taken to hospital twice with anxiety after her mother’s death.
In January, police said Brown was found in a bathtub in the suburban Atlanta home she shared with Nick Gordon, the man she called her husband. A police report described the incident as a “drowning”.
Mr Gordon said at the time she did not appear to be breathing and lacked a pulse before emergency services arrived. Although she was found face down in her bath, the 22-year-old also had bruises on the front of her body.
Authorities later concluded that she had suffered injuries to her face and mouth in a car crash several days earlier, saying they were not the result of foul play.
Brown was placed in a medically-induced coma and had been breathing with the aid of a ventilator before she died on Sunday.
Medical examiners have since said a post-mortem will be needed to evaluate what led to her death.
Fulton County Medical Examiner’s Office said the time that had elapsed from when she was found in January will “complicate” its effort to reconstruct events.
“Interpretation of autopsy findings and other information will also be challenging,” it said in a statement. “However, an autopsy could be helpful to address questions which may arise about the cause of her unresponsiveness and eventual death.”
Frosty relations between Mr Gordon and Brown’s relatives came to a head in June, when her court-appointed representative sued Gordon, accusing him of misrepresenting his relationship with her.
He was alleged to have transferred $11,000 (£7,091) of Brown’s funds into an account controlled solely by him while she was in hospital but was never charged.
As her health deteriorated last month, US authorities said they would be reviewing the circumstances of her condition “with greater interest”.
Bobbi Kristina’s tragedy echoed the circumstances of Whitney Houston’s tragedy: The 48-year-old former superstar was found dead in a bathtub at the Beverly Hilton hotel on Feb. 11, 2012.
Authorities examining Houston’s death found a dozen prescription drug bottles in the hotel suite. They concluded that Houston accidentally drowned. Heart disease and cocaine use were listed as contributing factors in her death.
The 48-year-old singer had struggled for years with cocaine, marijuana and pills, and her behavior had become erratic.
Daughter Krissi butted heads with family members after her mother’s death over her inheritance, her relationship and other disagreements, and tweeted often about missing her “mommy.”
Often seen as headstrong and determined to make it on her own in the music world, Krissi, who was born in Livingston, N.J., grew up with two parents who battled demons including drugs and alcohol during their 14-year-marriage, which ended in 2007. Their stormy union was documented in the 2005 Bravo TV reality series Being Bobby Brown.
Krissi then went on to be shown drinking on-camera during the filming of the 2012 Lifetime special, The Houstons: On Our Own.
At the time, Pat Houston told Barbara Walters that there was nothing wrong with it. “Cameras have been following since she was born. It’s not exploitation of any kind.”
In 2013, Cissy Houston addressed how her daughter’s death continued to adversely affect her granddaughter.
“Of course I worry about her,” Cissy told People.
“It doesn’t mean that she is going to follow her (mother’s) same path. She could but anybody could. I don’t want to jinx her. I’m trying to make sure she doesn’t.”
While living in Atlanta with Gordon, Krissi had more troubles. In 2013, the two were evicted from an apartment after multiple noise complaints from a neighbor.
Last year, Bobbi Kristina launched an angry Twitter rant against director Angela Bassett for not including her in the Whitney biopic for Lifetime.
Krissy was in the lobby of the Beverly Hilton when word came that her mother had died upstairs.