However, another of her sons, Jermaine, took to Twitter Saturday night to dispel reports his mother is missing, CNN reported Sunday.
"I want to reassure everyone ... that Mother is fine but is resting up in [Arizona] on the orders of a doctor, not us," he said.
Paris Jackson -- Michael Jackson's 14-year-old daughter -- said she's been trying to call her grandmother for a week, but her aunts Rebbie and Janet tell her she can't speak to Katherine, the elder woman's lawyer, Sandra Ribera, said.
"Yes, my grandmother is missing. I haven't spoken with her in a week. I want her home now," Paris tweeted.
Paris later added a doctor who testified on behalf of Dr. Conrad Murray -- who was convicted of involuntary manslaughter in Michael Jackson's death -- is taking care of her grandmother.
A nephew of Katherine, identified by CNN as Trent, filed a missing person's report with the Los Angeles County Sheriff's Department, TMZ reported.
The department has issued a statement asking the 82-year-old woman to contact them.
"Katherine Jackson is reportedly with family members," the statement said. "Late Saturday night, a different family member reported that he was unable to speak with her and is concerned for her well being. Deputies are continuing to make efforts to reach her and ask that she contact the Malibu/Lost Hills Sheriff's Station of the Los Angeles County Sheriff's Department."