Cheryl Hines praised Ethel Kennedy's "charisma, wisdom and strength" as she paid tribute to her late mother-in-law.

Activist Ethel, the widow of trailblazing politician Robert F. Kennedy and sister-in-law of former president John F. Kennedy, died on Thursday at the age of 96 following complications from a stroke she suffered last week.

Cheryl is married to Ethel and Robert's son Robert F. Kennedy Jr., and honoured the Kennedy matriarch's legacy on X.

"My mother in law, Ethel Kennedy, Bobby's mother, passed this morning. It has been my great honor to have shared laughter and love with Ethel," she began. "Her charisma, wisdom and strength will live on with me in every memory of her.

"Bobby and I spent many warm nights in Hyannis Port having dinner with her and hearing stories from her extraordinary life. She always made me laugh. She was never too serious except when she needed to be. She dressed to nines with bare feet. She will be missed. My love is with the family."

Ethel was only 40 when her husband was gunned down in 1968. His assassination came less than five years after his brother was shot and killed while serving as America's leader.

She went on to start nonprofit human rights advocacy organisation Robert F. Kennedy Human Rights soon after.

Ethel and Robert married in 1950 and welcomed 11 children, though tragically their sons David and Michael passed away in their adult years.

A statement released by the family reads: "It is with our hearts full of love that we announce the passing of our amazing grandmother, Ethel Kennedy.

"Along with a lifetime's work in social justice and human rights, our mother leaves behind nine children, 34 grandchildren, and 24 great-grandchildren, along with numerous nieces and nephews, all of whom love her dearly."

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