Joanna Cook Moore (November 10, 1934 – November 22, 1997) was an American film and television actress best known for her guest roles on the popular television shows of the 1960s, most notably as Sheriff Andy Taylor's love interest, Peggy "Peg" McMillan in four episodes of The Andy Griffith Show. She was married to actor Ryan O'Neal and is the mother of Tatum O'Neal. She is often credited as Joanna Moore.
She was born Dorothy Cook, the elder of two daughters, in Americus, Georgia to Henry Cook, an atomic scientist, and Dorothy English Cook. When she was a child, her parents and younger sister were involved in a fatal car accident. Her mother and sister died immediately, while her father died a year after the accident from the injuries he sustained. For a time, Cook was raised by her grandmother until she became mentally and physically incapable. Cook was then adopted by a wealthy local family and changed her name from Dorothy to Joanna.
As a teen, she married, and quickly divorced, Willis Moore. After the divorce, she attended Agnes Scott College in Decatur, Georgia. While attending college, she entered and won a beauty contest and was brought to Hollywood. Cook Moore's acting