Complex sentence: It has been suggested that she renounced her lifelong atheism, and become a Roman Catholic before her death (although her family do not support this theory), and is interred at Rookwood Cemetery in the family plot.
Split into simpler sentences: It has been suggested that she renounced her lifelong atheism and become a Roman Catholic before her death (although her family do not support this theory). She is interred at Rookwood Cemetery in the family plot.