Princess Mary was devoted to her children and to her public duties. She left her children in the care of a nanny, Charlotte "Lalla" Bill, and taught her children history and music. With her public duties, she was equally devoted, becoming Patron of a number of charities. When her father-in-law became King Edward VII, Prince George and Princess Mary undertook an eight-month tour of the British Empire. No royal had undertaken such a big tour before. Princess Mary broke down in tears at the thought of leaving her children, though they were in the care of their doting grandparents. 