AJ Mclean's role in Aaron Carter's rehab revealed

AJ Mclean recalled his involvement in Aaron Carter's attempts to recover from addiction.

In the upcoming documentary Aaron Carter: The Little Prince of Pop, the Backstreet Boys member opened up about his efforts to get him into rehab.

"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 added, "I was shocked, but I was happy, and he checked into a treatment center in Malibu."

"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," he added. 

On May 1, the documentary will release on Hulu. Backed by ABC News Studios, it shows the I'm All About You singer's story from his prime time in the music industry to his mental health battles.