Doug McCain, the eldest son of the late Senator John McCain, has died suddenly at the age of 66, leaving one of America’s most famous political families in mourning once again.

His sister, Meghan McCain, confirmed the heartbreaking news Sunday in an emotional tribute shared online, honoring the brother she described as full of life, humor, and warmth.

“I am deeply saddened to share the news of my brother Doug McCain’s sudden passing,” Meghan wrote in her statement on May 24.

She remembered Doug as “a truly wonderful, joyful man” who brought “humor, fun, and great conversation to every room.”

For Meghan, the loss is another painful blow for a family that has already endured years of public grief following the death of their father, Senator John McCain, in 2018.

No cause of death has been publicly revealed.

Doug McCain was part of the well-known McCain family legacy, though he lived a far more private life than some of his famous relatives.

He was born to Carol Shepp, who later married John McCain in 1965. John McCain adopted Doug and helped raise him as part of the family that would go on to become one of the most recognizable names in American politics.

Doug also followed the family’s long military tradition and served for years as a Navy pilot.

While John McCain became a national figure through his decades in the Senate and his 2008 run for president, Doug largely stayed out of the political spotlight.

Unlike Meghan, who became a television personality and outspoken conservative commentator, Doug kept a quieter profile and focused on his family and private life.

Still, his connection to the McCain name placed him within one of the most closely watched political families in the country.

John McCain died in 2018 at age 81 after battling brain cancer.

The longtime Arizona senator was remembered as a decorated Navy veteran, former prisoner of war, and political “maverick” who often broke with his own party.

Before his years in Washington, McCain served as a Navy pilot during the Vietnam War. In 1967, his plane was shot down over Hanoi, and he spent more than five years as a prisoner of war.

That experience became a defining part of his life story and helped shape his image as one of America’s most famous war heroes turned politicians.

He later served six terms in the U.S. Senate and became the Republican presidential nominee in 2008, running against Barack Obama.

Now, the McCain family is grieving again.

Doug is survived by his wife, Ashley; his children, Caroline and Shepp; daughters-in-law Ellie and Emily; his grandson Teddy; and his mother, Carol.

Meghan ended her tribute by reflecting on the deep bond she shared with her late brother and the memories their family will carry forward.

For a family so often seen through the lens of politics, Doug’s death is a deeply personal tragedy — the sudden loss of a husband, father, grandfather, son, and brother who meant far more to his loved ones than any famous last name.