Meghan McCain and her family are grieving the unexpected death of her stepbrother, Douglas Shepp McCain. Douglas was the oldest adopted child of the late Senator John McCain, passing away at 66.

According to his funeral home obituary, Doug McCain died on Wednesday. The cause of his sudden death has not been disclosed. Meghan McCain expressed her sorrow on X, stating, “I am deeply saddened to share the news of my brother Doug McCain’s sudden passing. He was a truly wonderful, joyful man who supported me throughout my life.” She reminisced about his humor and the joy he brought into every room, expressing her intention to cherish their memories.

The McCain Institute also shared condolences, acknowledging his contributions as a Navy pilot and a dedicated patriot, following in his father’s footsteps. His role as a friend to alumni of Senator McCain’s Institute and campaigns was highlighted in their tribute.

Born on October 4, 1959, in Pensacola, Florida, Doug McCain spent his formative years in Jacksonville. Active in sports, he engaged in surfing, baseball, and soccer. After finishing high school at Jacksonville Episcopal High School in 1977, he pursued systems engineering at the University of Virginia. Here, he joined Navy ROTC and met Ashley Jardine, his future wife.

After graduating in 1982, McCain served in the Navy for six years, flying A-6 Intruders. He later transitioned to a longstanding career with American Airlines, where he found his passion, eventually becoming a captain.

Doug McCain was John McCain’s adopted son from his first marriage to Carol Shepp McCain. John McCain, a decorated Navy aviator and POW, represented Arizona as a U.S. Senator and was the Republican presidential nominee in 2008. He passed away in 2018.

Described as a loyal friend and cherished family member, Doug earned the nickname “World Book” for his vast knowledge. His obituary recalls his love for golf, boasting a family record of three holes-in-one. McCain’s love and loyalty to his family and friends will be remembered warmly.

Doug is survived by his wife of 40 years, Ashley Jardine McCain, daughter Caroline McCain Hendrickson, son Douglas Shepp McCain Jr., and grandson Teddy. Additional survivors include his mother, Carol Shepp McCain, brother Andy McCain, sister Sidney McCain, stepmother Cindy McCain, and stepsiblings Meghan, Jack, Jimmy, and Bridget.

The family plans private services. A memorial gathering is scheduled for Saturday, May 30, at the Princess Anne Country Club in Virginia Beach, Virginia.