Garp is the main character in
John Irving's book
The World According to Garp.
The 1982 movie had Robin Williams playing T.S. Garp, a budding, sheltered writer who learns from his overly strong mother figure (in the movie played by Glenn Close) in the face of random violence and feminism.
Garp is the illegitimate son of nurse Jenny Fields and one of her patients, a pilot who died before Garp was born. Garp grew up insisting he knew his father, and wanting to have any possible connection to him.
As he grows up, Garp does not exactly have an easy life. He falls in love with and eventually marries the daughter of his wrestling coach. His short stories are eventually published and widely respected. But his mother has her own writing career; she publishes a feminist manifesto and becomes a hero to battered and distressed women everywhere. Garp gets a more unwelcome fame, becoming known as the illegitimate son of the most famous feminist writer of the times.
Things then get worse. Although Helen and Garp have two wonderful sons, Helen begins having an affair. Jenny moves in with a houseful of distressed women. And then Garp, in his anger, makes a horrible mistake that affects his whole family.