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Upon being confirmed in 1966, she adopted Veronica as a confirmation name. She was raised in the Detroit suburbs of Pontiac and Avon Township (now Rochester Hills). Months before her mother died of breast cancer, Madonna noticed changes in her behavior and personality, although she did not understand the reason. Her mother was at a loss to explain her medical condition, and often began to cry when Madonna questioned her about it. Madonna later acknowledged that she had not grasped the concept of her mother dying.

Which disease did her mother passed away from?
breast cancer