Los Angeles (CNN) -- Michael Jackson's ex-wife Debbie Rowe is set to testify in the AEG Live wrongful death trial Wednesday, lawyers for the concert promoter said Monday.
Rowe is expected to be questioned about Jackson's drug use during the 1990s when she traveled with him, married him and bore his two oldest children.
She will be called as the next witness in the Los Angeles courtroom after an economics expert concludes his testimony about the financial support Jackson would have provided his mother and three children had he not died four years ago.
Jackson's youngest brother made an unsuccessful effort to reach the singer in his last weeks because of family concerns about his drug use, according to testimony Friday.
Lawyers for the concert promoter accused of liability in Jackson's death want to show that the pop icon was a secretive drug addict who was even beyond his family's help.
Jurors watched video of Randy Jackson's questioning by the AEG Live lawyers about failed interventions he led because of his concerns about Michael Jackson's use of painkillers in the last decade of his brother's life.
Jackson died from an overdose of the surgical anesthetic propofol that a doctor told police he was using to treat his insomnia as he rehearsed for a comeback tour four years ago. Jackson's mother and three children are suing the concert promoter, contending it negligently hired, retained or supervised the doctor convicted of involuntary manslaughter in his death.
Randy Jackson testified that he and his father, Joe Jackson, were turned away from the gates of Jackson's rented Los Angeles mansion on Carolwood Drive, the home in which he died weeks later. They were concerned because of "reports to me that he didn't look too good," he said.
"After I had heard this, I said, 'Come on, let's go. We're going over there,' " he testified.
Other witnesses, including Jackson's makeup artist and the show director, have testified that Jackson suffered physical deterioration in the last two months of his life.
"There was a drug issue," Randy Jackson said, explaining why they wanted to reach him. "He wasn't eating. All of these things were happening at the same and, you know, a lot of pressure."
He said he wanted to persuade his brother to leave rehearsals and enter a drug rehab program in San Francisco.
"Of course my brother wouldn't let me through because he wouldn't want me to see him like that," he said. The security guard told him his brother was not at home, he said.
Jackson lawyers do not dispute that Michael Jackson had a drug dependency problem at times, but they say he went long periods of time without taking painkillers. The entertainer publicly acknowledged his dependency when he cut short his Dangerous tour to enter a rehab program in 1993.
The drug use was connected to two decades of pain stemming from scalp burns suffered while filming a Pepsi commercial and several onstage accidents on tour, they say. He also used prescription sedatives to help him sleep, especially during the pressure of touring, they argue.
The pressure was on again as Jackson prepared for his "This Is It" concerts set to debut in London in July 2009, they say. Jackson was getting nightly infusions of propofol in a desperate effort to cure his insomnia, which a sleep expert testified disrupted his natural sleep cycles and caused his physical and mental decline.
AEG Live executives created an ethical conflict of interest by hiring Dr. Conrad Murray as Jackson's full-time physician for $150,000 a month, the Jackson lawsuit contends. Murray could not refuse Jackson's demands for propofol infusions since he was deeply in debt and could not risk being fired from the lucrative job, they argue.
AEG Live lawyers say it was Jackson who chose and controlled Murray, not the company, and they had no way of knowing about the dangerous treatments he was giving the singer in the privacy of his bedroom.
While Randy Jackson was questioned for several hours by AEG Live lawyers, only about an hour of the video was shown to jurors Friday. Most of it focused on his repeated attempts to interrupt his brother's use of painkillers.
"I wrote letters to my family about his problem and that we had to do something to help," Randy Jackson testified. The letters would tell his parents, brothers and sisters that 'he's an addict,' and at this point, addicts aren't so responsible for what they do. So this is where the family needs to step in and do something about it because their desire becomes physical."
Jackson testified that he "staged several interventions," including in Taiwan, New York, Las Vegas and Los Angeles.
"Four or five" of those attempted interventions were at Jackson's Neverland Ranch between 2004 and 2006 -- around the time of the child abuse trial in Santa Barbara County, California, he said.
MJ's 'pajama day' in court
Randy Jackson said he was able to get his brother off of drugs at one point, but he resumed just before the child molestation trial began in a Santa Maria, California, courtroom in 2004. "He was really scared."
He fired Jackson nanny Grace Rwaramba because he suspected she was supplying his drugs, he said. "Whenever she's around, he's wasted."
He asked older sister Rebbie Jackson to stay close to their brother, he said, telling her, "Make sure you watch everything he does, because I have to get him in this courtroom every day and see this thing through."
Randy Jackson gave new insight into what happened that infamous day of the trial when Michael Jackson showed up late for court wearing pajamas. At the time, the singer blamed a back injury suffered when he fell in the shower, which sent him to a hospital that morning.
His brother testified, however, it was "because he didn't want to go to court."
"I went to the hospital and he said to me, he says, 'I don't know what you're thinking. I'm not walking into that courtroom, so don't even think about it, Randy,' " he testified. "And I said, 'OK.' I said, 'But you're going to court.' He goes, 'No, I'm not.' "
Randy Jackson blamed the nanny for supplying "some kind of patch" that had drugs.
Jackson also described an incident in which his brother had a bad reaction to a sedative while at a Beverly Hills home in 2005. The nanny called him, saying, "You need to get over here. Something's not right," he testified. A doctor who lived nearby paid a house call and treated him, he said.
He said his brother would "kind of hide from me" because he didn't want him to know about his drug use, Jackson said.
Monday is the start of the 16th week of testimony in the trial, which the judge told jurors could last until the end of September.