"They could have called me," Katherine Jackson, 83, said. "He was asking me for his father. My grandson told me that his daddy was nervous and scared."
Her comments came under questioning from her attorney, Brian Panish.
Moments earlier, an attorney for AEG Live had questioned why the Jackson family matriarch -if her purpose for filing the lawsuit was to find out the truth about her son's death, as she had testified - hadn't read through thousands of pages of deposition testimony, or asked her grandchildren about what happened in her son's rented mansion before his June 2009 death.
She later said that while she could have asked her grandchildren about some issues, she didn't want to bring it up with them.
She also said that she didn't see a photograph of her son shot six days before her his death until after the trial started.
Katherine Jackson at first didn't seem to want to look at the photo, which has been repeatedly displayed during the trial and shows her son wearing a T-shirt, his arms thin and bones visible in his upper chest.
Katherine Jackson claims AEG Live failed to properly investigate Dr. Conrad Murray, who was later convicted of involuntary manslaughter for giving the singer an overdose of the anesthetic propofol.
AEG defense attorney Marvin S. Putnam told jurors during opening statements in the negligence lawsuit in April that the case centered on personal responsibility - specifically Michael Jackson's decision to ask Murray to administer propofol as a sleep aid while he prepared for his shows.
AEG Live denies it hired the doctor or bears any responsibility for Jackson's death.
Katherine Jackson said she believes AEG Live hired Murray, not her son. She said she never heard of the cardiologist until her son died, and indicated that she felt Murray bore responsibility for her son's death.
"Even though he asked for it, he could have said no," she said of Murray.
Putnam also asked Katherine Jackson about her son's payments to her over the years. She said he directly paid many of the expenses on her home and would occasionally give her cash as a gift.
Saying she didn't keep track of the payments, Katherine Jackson appeared to being annoyed at the questions.
"What does this have to do with the death of my son," she asked Putnam.
The attorney also asked her about conversations she had with her son about prescription drug use.
She said she asked him about it when he lived in Las Vegas and he denied he was abusing prescription medications.
"I'm a mother, quite naturally he denied it," she said. "He wouldn't want me to think that."
She said she wasn't surprised by his denial and likened the situation to a child who'd disobeyed his mother while playing outdoors.
Putnam said Jackson was a 50-year-old man at the time of his death. "He's still my child," Katherine Jackson said. "He'd still want me to hold his respect."
She said she was aware her son took medications for pain in his back and scalp after he sustained injuries over his career. She said she never saw signs that her son was abusing medications, including when she and several of her children went to the singer's Neverland Ranch in 2002 for an intervention.
Her son was fine but upset that they thought he had a problem, she said.
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