'American Idol' alums honor Mandisa in powerful tribute: Watch here

Three "American Idol" alums took to the stage Monday night to honor one of their own, Mandisa, the season 5 alum who died earlier this month at the age of 47.

Melinda Doolittle (season 6), Danny Gokey (season 8) and Colton Dixon (season 11) performed a rendition of the Mary Mary song "Shackles (Praise You)" as a tribute to the late gospel singer and Grammy winner.

The song choice was apt, as Mandisa performed it on the "American Idol" stage in 2006.

Doolittle honored her friend after the performance, telling host Ryan Seacrest the two knew each other for over 20 years.

"We started out singing background in sessions together," she said. "Then she got on 'Idol' and I cheered for her. Then I came the next season and she cheered for me. That is my girl through and through."

Gokey spoke of how he believed Mandisa would like to be remembered.

"One of the things that sticks out to me is she was a fan of people. She was a cheerleader for other people's music," he said, recalling a time in his career she supported him. "She always was that person."

Dixon shared why he believed "Shackles (Praise You)" was the perfect song to dedicate to Mandisa.

"I think that song sums up her life," he said. "I think she came in praising. I think she left praising. We're going to miss her, but our loss is heaven's gain."