Complex sentence: The young Zélie first appeared on stage at the age of nine but her parents forbade her to embark on a professional musical career until the Swedish singer Christina Nilsson heard her sing and persuaded the de Lussans to change their minds.
Split into simpler sentences: The young Zélie first appeared on stage at the age of nine but her parents forbade her to embark on a professional musical career. The Swedish singer Christina Nilsson heard her sing and persuaded the de Lussans to change their minds.