Complex sentence: After The O'Kanes disbanded in 1990, both O'Hara and Kane recorded solo albums of their own; in addition, O'Hara has continued writing songs for other country music artists.
Split into simpler sentences: After The O'Kanes disbanded in 1990, both O'Hara and Kane recorded solo albums of their own. In addition, O'Hara has continued writing songs for other country music artists.