A recording of Michael Jackson bemoaning his unhappy childhood has been played to the trial of the doctor charged with his death. In the audio recorded six weeks before the star's death, an apparently drugged Jackson tells Conrad Murray about his plans to stage a series of concerts. Jackson says the shows in London will be for children as he did not have a childhood. Dr Murray is charged with the involuntary manslaughter of Jackson. The clip, already aired in last week's opening statements, was played in full on Wednesday at the trial in Los Angeles. 'I am asleep' Jackson's slurred voice is heard telling Dr Murray of plans to build a children's hospital - the biggest in the world - after the concerts, billed as This Is It. It would be an achievement, Jackson said, that even Elvis Presley and The Beatles did not match. "That will be remembered more than my performances. My performance will be up there helping my children and always be my dream," Jackson is heard telling his doctor in the 10 May 2009 recording. "I love them. I love them because I didn't have a childhood... I feel their pain. I feel their hurt. I can deal with it." With Dr Murray murmuring agreement, Jackson refers to the children of the world as "angels" and says: "God wants me to do it. I'm gonna do it, Conrad." Toward the end of the recording, there is a period of silence before Dr Murray asks: "You OK?" Eight seconds pass before Jackson mumbles: "I am asleep." The more than four-minute audio recording was found on Dr Murray's mobile phone by forensic digital expert Stephen Marx. The tape was played by prosecutors to show that Dr Murray knew for weeks the adverse effects of heavy sedatives he was administering to Jackson. The prosecution says Dr Murray was distracted while he should have been monitoring Jackson. The doctor's lawyers say Jackson self-administered a lethal dose of propofol, a powerful sedative which the singer was using as a sleeping aid. Witnesses in the past two days included several of the doctor's mistresses and his current girlfriend, Nicole Alvarez. Prosecutors say she received shipments of propofol at her apartment on Dr Murray's behalf. She said she never knew what was being sent. The trial is expected to last around five weeks. If convicted, Dr Murray could spend up to four years in prison and lose his licence to practise medicine.