Complex sentence: Margaret died in childbirth with George, and so at age ten Frances was sent to live with a cousin of her mother's who was master of the Charterhouse in Kingston-on-Hull, Yorkshire.
Split into simpler sentences: Margaret died in childbirth with George, and so at age ten Frances lost her mother. She was sent to live with a cousin of her mother's who was master of the Charterhouse in Kingston-on-Hull, Yorkshire.