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Speaking to interviewer Robin Roberts for US news show 20/20, Bobby spoke about the similarity between their deaths, saying: "The same thing that happened to my daughter, it happened to Whitney."
Bobby spoke about Whitney and Bobbi Kristina in an interview
Bobbi Kristina died at the age of 22 after she was found unconscious in a bathtub, spending six months in a medically induced coma before she tragically passed away. Her mother Whitney, who had long battled addiction, died three years earlier after she was found unresponsive in a bathtub.
In the emotional interview, which will released in full on 7 June, the R&B singer said: "The hardest thing I had to do in my life was tell my daughter to let go. My baby's gone. I thank God I'm still here."
At the time of Bobbi Kristina's passing, her father released a statement to Entertainment Tonight, writing: "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. Our loss is unimaginable.
The full interview will air on 7 June
"We thank everyone for the prayers for Krissy and our family as we mourn my baby girl."
The family confirmed that Bobbi Kristina had passed away in 2015, writing on Whitney's Facebook page: "Bobbi Kristina Brown passed away Sunday, July 26 2015 surrounded by her family. She is finally in the arms of God.
"We want to again thank everyone for their tremendous amount of love and support during these last few months."
Mark your calendars for Tuesday June 7th - Bobby Brown speaks to @RobinRoberts in a special #abc2020!https://t.co/yQnJh5AMST— 20/20 (@ABC2020) June 2, 2016