Complex sentence: When he was ten, in 1965, his family moved to Worthington, Ohio, and when he was 18, in 1973, they moved to Missoula, Montana, where his father became Director of the School of Music at the University of Montana.
Split into simpler sentences: When he was ten, in 1965 his family moved to Worthington, Ohio. In 1973, when he was 18, they moved to Missoula, Montana, where his father became Director of the School of Music at the University of Montana.