The Backstreet Boys alum also opened up about his own battle with addiction, "I almost lost my marriage, I almost lost my band, I almost lost my life."
AJ McLean is opening up about the time he picked up Aaron Carter's call for help.
The 45-year-old Backstreet Boys alum recalled the moment he helped the "I Want Candy" singer get a handle on his substance abuse in ABC's upcoming documentary, "Aaron Carter: The Little Prince of Pop."
"2017, Aaron reached out to me, asked me for help. I said, 'Look, if you get on a plane, come out to L.A., I will make sure you get into treatment.' And he showed up," McLean said in the clip. "I was shocked, but I was happy, and he checked into a treatment center in Malibu."
He continued, "A couple days later, I talked to him, and then he kind of went off the map. I think it was maybe two weeks, so I called my friends at the treatment center, and they said he checked himself out."
Elsewhere in the preview, McLean, who was in the iconic '90s boy band with Aaron’s brother Nick Carter, also opened up about his own struggles with addiction.
"I was a functioning addict. I had been in and out of the rooms since 2001, so for 22 years I've been battling my own s—," he continued. "I almost lost my marriage, I almost lost my band, I almost lost my life. The last time I relapsed, which would be 18 months ago, my youngest daughter was kind of the nail in the coffin for me."
The last straw was when his daughter could no longer recognize him by smell and the "Everybody" singer knew he had to make a change.
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View Story"She said I didn't smell like her dad. That was enough," he admitted. "That pretty much did it for me and I have stayed sober since and I plan on staying sober. It's a daily thing."
On November 5, the "Aaron's Party" singer was found dead at his Lancaster, CA home. TMZ was first to report the news. Several sources told the outlet that Carter's body was discovered in a bathtub.
"Aaron Carter: The Little Prince of Pop" will follow the life of the child star and the height of his popularity in the early 2000s. The documentary will also cover his eventual mental health struggles, family drama and his battle with addiction as well as his death.
The film will be available to stream on Hulu on May 1 and will feature interviews from various figures in Carter’s life, including his ex-fiancee Melanie Martin and Christy Carlson Romano.