Roberta will also be present for her son’s burial at the U.S. Naval Academy Cemetery in Annapolis, Maryland, according to NBC News White House correspondent Kelly O’Donnell.
Roberta, who lives in Washington, D.C. and did not attend Wednesday’s memorial service for her son at the Arizona State Capitol, is “doing well,” O’Donnell reported.
As Roberta grieves the loss of her son, who died of brain cancer at the age of 81 on Saturday, a close McCain family friend tells PEOPLE that she is a “very strong woman” who’s retained her “spunky” spirit.
“She is all there, mentally, and is still going strong at 106,” the friend says. “She outlived her 81-year-old son. That tells you a lot. But it’s a tough blow to bury your child.”
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The insider noted that while Roberta did not travel to Arizona following Friday’s news that her son would be ceasing medical treatment for glioblastoma — the most aggressive form of brain cancer, with which he was diagnosed in July 2017 — the two did speak on the phone recently, and she knew the extent of her son’s illness.
The friend says Roberta was her son’s “biggest supporter and the leader of his fan club.”
“She was incredibly proud of him,” the source adds. “His mommy loved him. He knew that.”