Dr. Conrad Murray
Dr. Conrad Murray listens to testimony during his trial in the death of pop star Michael Jackson in Los Angeles Reuters

A recording of an apparently drugged Michael Jackson was played on Wednesday in the manslaughter trial of the singer's doctor, with the King of Pop saying he wanted to help kids because he didn't have a childhood.

The May 2009 conversation between the singer and Dr. Conrad Murray, recorded on the physician's cellphone, marked one of the most dramatic moments in the week-old trial in Los Angeles.

Jackson's siblings Jermaine, Randy and Rebbie were among those in court listening to the recording. Jermaine Jackson wiped away tears with a tissue.

Michael Jackson is heard speaking slowly, in a low and at times incoherent voice, slurring his words.

My performances will be up there helping my children and always be my dream, Jackson said. I love them because I didn't have a childhood. I had no childhood. I feel their pain.

Prosecutors are seeking to prove through the tape that Murray knew the effects of the drugs they claim he was giving Jackson, well before the singer died in his care on June 25, 2009.

'I AM ASLEEP'

Murray is charged with involuntary manslaughter -- or criminal negligence -- in Jackson's death at his Los Angeles mansion from what medical examiners have said was an overdose of the powerful anesthetic propofol combined with sedatives.

The doctor has admitted giving Jackson propofol that day as a sleep aid. But his attorneys claim that Jackson gave himself an extra, fatal dose of propofol when Murray was out of the room.

At the end of the tape played on Wednesday, Jackson stops talking and Murray asks him, You OK? Then there is another pause and Jackson responds, I am asleep.

The tape was made by Murray as Jackson prepared for a series of 50 planned comeback concert dates in London titled This Is It.

Elvis didn't do it. Beatles didn't do it. We have to be phenomenal, Jackson is heard saying. He goes on to say that he wants to use the profits from his shows to fund a children's hospital.

Gonna have a movie theater, game room, Jackson said, in describing his dream hospital. Children are depressed. The -- in those hospitals, no game room, no movie theater. They're sick because they're depressed. Their mind is depressing them.

Jackson said he felt God wanted him to pursue the project.

Murray has pleaded not guilty to involuntary manslaughter. He faces a maximum of four years in prison if convicted.