As Bobbi Kristina Brown remains in a rehab treatment center, the brother of her longtime boyfriend, Nick Gordon, has spoken out about claims that the couple was on drugs before the incident that leaves her now fighting for her life.

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Jack Walker spoke with AJ Collaway of Entertainment Tonight earlier this month and didn't hold back when it came to opening up not only about Brown and Gordon's struggle with substance abuse but said Brown's late mother Whitney Houston was involved.

"I would be on the phone with Nick and I would hear Whitney ask for the stuff," he confessed. "It was there before Whitney died."

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He said Gordon moved in with Houston and Brown when he was left with nowhere to go after his then roommate got in trouble and lost their apartment. Walker, who said he introduced Gordon and Brown, admitted he had his hesitancies about Gordon moving in with the iconic singer and her daughter. Walker also clarified that, "This wasn't something that just came about when Whitney died. It's been around before Nick."

Brown is currently getting treatment after she was found unconscious in her bathtub on Jan. 31. Walker said he found out right when it happened as Gordon called him. According to what Gordon told his brother, he and Brown went to a nightclub the evening before and got into an argument that carried over into the next morning.

Walker implied that Brown was trying to take her life. Houston was also found unconscious in a bathtub and died moments later back on Feb. 11, 2012.