Michael Jackson has been gone for four years, and the legal battles involving his estate and his family are just beginning.

Jackson’s children–along with his mother Katherine–are suing concert promoter AEG Live for negligently hiring Dr. Conrad Murray to oversee Jackson’s care during the last weeks of his life. Murray has been convicted of involuntary manslaughter in Jackson’s death after providing the music icon with a lethal mixture of anesthetics.

16-year old Prince Jackson was just 12 when he accompanied his father to the hospital on the day he died, and will likely stand trial on Wednesday. Dr. Gordon Matheson took the stand today as an expert in medical conflicts and said that Murray, who was nearly $1 million in debt at the time he took the high-paying job as Jackson’s personal doctor, might have been inclined to push Jackson to do shows for AEG Live despite his failing health simply because he needed the money.

Murray had been giving Jackson high doses of propofol–at the singer’s request–to help him sleep at night. But the drug keeps the user from having deep REM sleep, and the effects on Jackson’s body were obvious.

“The symptoms that Mr. Jackson was exhibiting were consistent with what someone might expect to see of someone suffering from total sleep deprivation over a chronic period,” Dr. Charles Czeisler, a Harvard Medical School sleep expert, testified Friday at the trial.

Prince will be the only one of the children to testify in court; Paris has recently had personal issues and attempted suicide earlier this month.