When Anderson was 12, her father received a head injury while working at the Reading Terminal before Christmas 1909. Soon afterwards her father died, following heart failure. He was 37 years old. Marian and her family moved into the home of her father's parents, Benjamin and Isabella Anderson. Her grandfather had been born a slave and had been emancipated in the 1860s. He relocated to South Philadelphia, the first of his family to do so. When Anderson moved into his home, the two became very close, but he died just a year after the family moved in.