Michael Jackson's family was aware of his drug addiction, intervened to stop him but was not successful, Janet Jackson said in an interview airing tonight on ABC's Good Morning America.

I did [intervene], Jackson told ABC's Good Morning America anchor Robin Roberts.

Of course, that's what you do. Those are the things that you do when you love someone. You can't just let them continue on that way. And we did a few times. We weren't very successful.

Despite of the efforts, Jackson died on June 25, and a mix of prescription drugs were found in his body along with a powerful sedative called Propofol.

Jackson's sister Janet said she believes Michael denied his addiction.

The interview airs today at 10:00 p.m. at GMA's In the Spotlight.