David Kaczynski

David Richard Kaczynski (born October 3, 1949) is an American charity worker. He is the younger brother of the domestic terrorist and mathematician Ted Kaczynski (1942–2023), also known as the Unabomber.

His memoir, ''Every Last Tie: The Story of the Unabomber and His Family'', details both his relationships with his brother and their parents, and his and his wife Linda's decision to report their suspicions of Ted to the Federal Bureau of Investigation (FBI), which ultimately led to his arrest in 1996. The decision prompted Ted to cease all communication with his family, including rejecting all of David's attempted correspondence during his imprisonment. Provided by Wikipedia