Olivia d'Abo (born 22 January 1969) is an English-American actress and singer/songwriter, best known for portraying Kevin Arnold's rebellious teenage sister Karen in The Wonder Years and Nicole Wallace, a recurring villain in Law & Order: Criminal Intent. D'Abo's film debut was in the supporting role of Princess Jehnna in Conan the Destroyer, released in June 1984. Just two months later, she also appeared topless aged 15 in the supporting role of the peasant girl Paloma in Bolero. From 1988, d'Abo was in the main cast of The Wonder Years in the first four seasons. Her character Karen Arnold was the hippie sister in the family. In 1992, she guest starred in the Star Trek: The Next Generation episode 'True Q' as Amanda Rogers.
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