Bobby Brown and the late Whitney Houston's daughter is fighting for life in an Atlanta, Georgia hospital more than a month after Gordon found his girlfriend unresponsive and face down in a bathtub at their home in nearby Roswell.

Her boyfriend has been banned from visiting her in hospital by Bobby Brown and members of the Houston clan, and last week (ends06Mar15) his mother revealed the embattled 20-something has attempted to take his own life twice in the weeks following his girlfriend's near-drowning incident.

Now, Jack Walker Jr., who served as Gordon's dad while he was dating his mother throughout his youth, tells U.S. news show Access Hollywood he fears his ex's son will end his life if Bobbi Kristina doesn't survive.

He says, "It hurts a lot, seeing him (Gordon) in pain... He's hurt so bad... It's hard for him each day. He doesn't know if he can make it another day. It's getting harder and harder.

"He's out of control right now. He's hurt. He's hitting rock bottom with this... If something happens to Bobbi Kristina... if she doesn't pull through then I will fear for my son's life."

Walker, Jr. confirms Gordon has entered a rehab facility following an odd TV showdown with U.S. self-help guru Dr. Phil MCGraw, who was asked to stage an intervention as part of a planned interview with Gordon for his Dr. Phil show.

The tense chat, which aired in America on Wednesday (11Mar15), ended when an intoxicated and irritable Gordon stormed out as MCGraw attempted to urge him to seek professional help for a series of issues, including drug and alcohol dependency.