LOS ANGELES — A US judge on Wednesday gave temporary guardianship of late singer Michael Jackson's three children to his nephew TJ amid a bitter public dispute over the whereabouts of the family's matriarch.

Katherine Jackson, the late singer's mother, had custody of Paris, Prince Michael and Blanket, but Judge Mitchell Beckloff suspended that arrangement because she had left the family home in Los Angeles.

The family has been embroiled in legal and financial disputes since the pop star's sudden death in June 2009 from an overdose of Propofol, a powerful anesthetic.

The matriarch's whereabouts are still uncertain, with one member of the family reporting her missing -- but the singer's brother Jermaine insisting she was well and resting in Arizona.

"I want to reassure everyone ... that Mother is fine but is resting up in AZ on the orders of a doctor, not us," Jermaine Jackson tweeted.

Randy Jackson, another of the singer's brothers, on ABC's "Good Morning America" Wednesday repeated that Katherine had left Los Angeles on doctors orders.

Her doctor "wanted her to go somewhere where she couldn't be on the phone, and just cut off from the outside world for a few days," he said.

However, the affair has sparked a flurry of angry Twitter messages from Jackson's 14-year-old daughter, Paris.

On Sunday, she wrote: "Yes, my grandmother is missing. i haven't spoken with her in a week i want her home now."

And then on Tuesday, she posted: "9 days and counting... so help me god i will make whoever did this pay."

Prince Michael is 15 and Blanket is 10.

Lawyers for TJ Jackson, the 34-year-old son of Michael's brother Tito, and for Katherine Jackson told the judge they suspected the woman's disappearance was not voluntary.

TJ Jackson said he spoke with Katherine on Tuesday and that she was acting strangely.

"I've never heard my grandmother talk like that," he said in court. "I'd ask simple questions and she wasn't sharp."

Her absence has been portrayed in entertainment media as a kidnapping by Michael's siblings, who are allegedly furious they did not inherit any of the singer's assets.

On July 17, five of the siblings accused the estate's executors of forging Jackson's signature on the 2002 will that excluded them.

In a letter posted online, Tito, Randy, Jermaine, Rebbie and Janet write "the will, without question, it's fake, flawed, and fraudulent." Tito later withdrew from the group, according to celebrity news website TMZ.

The siblings say they have "evidence that undoubtedly supports and proves that Michael was absolutely not in Los Angeles, California on the date of his signature" in the will.

They demand the executors, John Branca and John McClain, "resign effective immediately," accusing them of having "failed to perform (their) duties."

However, TMZ has reported that the executors had paid off nearly all of the singer's $500 million debt with the income they generated from his assets.

In a statement, Branca and McClain wrote they are "saddened that false and defamatory accusations grounded in stale Internet conspiracy theories are now being made by certain members of Michael's family whom he chose to leave out of his will."