Paul Newman and his daughter Nell were slated to play the roles in Paper Moon (1973) that later went to Ryan and Tatum O'Neal. They bailed out when there was a change in Director (To Peter Bogdonavich).
Before Paper Moon, Nell (under the name "Nell Potts") was a young kid who had a starring role in "The Effects of Gamma Rays on Man-in-the-Moon Marigolds" (1972, directed by her father and co-starring her mother Joanne Woodward). It was a very depressing, but excellent film.
Nell Newman never had another role in showbiz. She's now running her late father's food empire. Tatum O'Neal won an Oscar for her role in Paper Moon.