Angela Margaret Cartwright (born September 9, 1952) is an English-born American actress primarily known for her roles in movies and television. Cartwright is best known as a child actress for her role as Brigitta Von Trapp in the Academy Award winning film The Sound of Music (1965). On television, she played Linda Williams, the stepdaughter of Danny Williams (played by Danny Thomas) in the 1950s TV series The Danny Thomas Show, and Penny Robinson, in the 1960s television series Lost in Space. Her older sister is actress Veronica Cartwright.
Angela Cartwright was born in Altrincham, Cheshire, England, in 1952. She made her first film appearance at the age of three years as Paul Newman's daughter in Somebody Up There Likes Me (1956), and appeared with Rock Hudson and Sidney Poitier in Something of Value (1957). After moving to the United States, Cartwright appeared for seven seasons in the CBS TV series The Danny Thomas Show, opposite comedian Danny Thomas. She remained close to Thomas after the series cancellation, until his death on February 6, 1991.