Answer
Emmy Rossum was only 16 years old when she landed her breakout role in the 2003 Clint Eastwood-directed film Mystic River. The American actress and singer portrayed the character of Katie Markum, the daughter of Sean Penn's character, Jimmy Markum. Rossum's performance in the film, opposite Sean Penn, Kevin Bacon, and Tim Robbins, garnered widespread critical acclaim and marked a significant turning point in her acting career.