John Blyth Barrymore was born on May 15, 1954 to John Drew Barrymore and Cara Williams. John Blyth is the grandson of the legendary John "The Great Profile" Barrymore and his third wife, actress Delores Costello. He is also the great-nephew of Lionel and Ethel Barrymore. John Blyth has three younger half-sisters, Blyth, Drew, and Jessica from his father's three subsequent marriages. He also has an older half-sibling from his mother, Cara Williams first marriage. John Blyth's father, John Drew, was a failed actor and suffered from a lifelong addition to alcohol and drugs, before dying of cancer in 2004. His mother was the star of Pete and Gladys and The Cara Williams Show. John Blyth is the father of John Barrymore IV and two young daughters. John Blyth Barrymore also attempted an acting career , but wisely, abandoned it after taking after his father in problems with drugs and alcohol. Today. he works in the technology field as a software developer.