Roberta McCain, 106, attends memorial services for son John McCain

Roberta McCain, John McCain's 106-year-old mother, attended a Phoenix memorial service for her son Thursday and is expected to attend upcoming services for the late senator at the Capitol, the National Cathedral and the Naval Academy, according to McCain aides.

She is expected to attend the formal ceremony at the US Capitol honoring her son's life and service to the nation on Friday morning. The late senator will lie in state at the US Capitol.

Roberta McCain is also expected to attend McCain's memorial service at the National Cathedral in Washington Saturday, where former Presidents Barack Obama and George W. Bush will deliver eulogies, as well as a private memorial service for her son at the US Naval Academy in Annapolis, Maryland, on Sunday.

The McCain matriarch was a frequent presence on the campaign trail when her son sought the presidency in 2008. A spirited woman, even in her advanced age, Roberta McCain has consistently traveled, including taking a trip to Europe in her 90s.

"Do you want me to sit around and play bridge every day? Or discuss my last knee replacement? Or pass around pictures of my grandchildren?" she told CBS News in a 2008 interview alongside her son, John. "Well, that isn't my choice of a way to live."

During his speech accepting the Republican presidential nomination in 2008, Sen. McCain credited his mother for raising him while his father, John McCain Jr., a Navy Admiral, was away.

"My friends, when I was growing up, my father was often at sea, and the job of raising my brother, sister and me would fall to my mother alone," McCain said. "Roberta McCain gave us her love of life, her deep interest in the world, her strength, and her belief that we're all meant to use our opportunities to make ourselves useful to our country."

He added, "I wouldn't be here tonight but for the strength of her character."

McCain told CBS News in 2008 that he and his mother become very close in his early years.

In his final book, "The Restless Wave," McCain wrote that his mother's "main attributes are enthusiasm, wanderlust, and good genes."

"Her vivaciousness is a force of nature," he wrote. "Even now, after a stroke has slowed her down, when her brisk pace is a memory and speaking can be a chore ... there's still a spark in her, a brightness in her eyes that would light up the world if she could resume her peripatetic life."

He continued, "I am my mother's son. I always have been."

Sen. McCain is also survived by his wife, Cindy, and seven children.

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