Complex sentence: She then became a resident singer at the Rialto Ballroom, Upper Parliament Street and next joined her three brothers in the Carrolls, a group who made several records during the Sixties.
Split into simpler sentences: She then became a resident singer at the Rialto Ballroom, Upper Parliament Street. Subsequently, she joined her three brothers in the Carrolls, a group who made several records during the Sixties.