Bobby Brown says he and Whitney Houston failed their daughter.

Bobby Brown

Bobby Brown

Bobbi Kristina Brown, the daughter of Bobby and the late singer Whitney passed away in July 2015, nearly six months after she was found unresponsive in a bathtub in her Roswell, Georgia, home, and Bobby admits he and her mother are partly to blame for her death.

Speaking to Robin Roberts in a new ABC '20/20' interview, he said: "We could have been better. We should have been better."

Bobby had a turbulent marriage to Whitney, who died in 2012 aged 48 after she was found unresponsive in a bathtub at a Beverly Hills hotel.

The iconic singer was found by medical experts to have died of an accidental drowning, although drug use was said to be a contributing factor to her ill-health.

Bobby has also battled drug addiction in the past and a mixture of marijuana, alcohol, a cocaine-related substance, sedatives, anti-anxiety medications and morphine were found in Bobbi's system when she was found unconscious.

Meanwhile, Bobby also went on to hit out at Nick Gordon, Bobbi's boyfriend.

He said: "It's not a mystery to me the same thing that happened to my daughter is what happened to Whitney. There is only one person around both occasions.

"He knows what happened. I don't know what happened that night, but he does."

Nick previously hit out at those who have blamed him for the deaths of Whitney and Bobbi who passed away in similar circumstances, three years apart.

He said: "Regardless of what everybody thinks, I made Krissy and Whitney's last few years on earth as happy as they would be.

"I gave them somebody to trust to, to talk to, to be there, someone genuine."

And he was especially scathing about Bobby, saying: "(Bobby) hurt his own daughter, not me. I was the one there for her while she was dealing with him not being there. He's not a reasonable person so I'm not planning on talking to him and I really don't want to."