Mary Courtney Kennedy Hill (known as Courtney) was born on September 9, 1956, in Boston. She is the fifth child of Robert F. Kennedy and Ethel Skakel Kennedy.

It was through her work at the Children's Television Network that she met ABC sports producer Jeffrey Robert Ruhe. The couple married on June 14, 1980, in Washington, D.C.. They were divorced in 1990.

She then married Paul Michael Hill in June 26, 1993, on a boat in the Aegean Sea. Paul Hill is an Irishman who was wrongly imprisoned for 15 years for IRA terrorism. Hill was one of the Guildford Four who were wrongly convicted of bombing two pubs outside of London. (The film In the Name of the Father was based on this case.) Reportedly, the two were introduced by her mother.

The couple has lived in Ireland since 2002. They have one child, a daughter named Saoirse Roisin Hill, born May 22, 1997, in Washington D.C.

Kennedy Hill is formerly a representative for the United Nations AIDS Foundation.