Lillie Evelyn Moller was born in Oakland, California, on May 24, 1878, to Annie () and William Moller, a builder's supply merchant. She was their second child and the eldest of the family's nine surviving children. Their first child, Anna Adelaide, had died at age four months. Her parents, of German ancestry, were well to-do. Educated at home until the age of nine, Moller began formal schooling in the first grade at a public elementary school and was rapidly promoted through the grade levels. She was elected vice president of her senior class at Oakland High School and graduated with exemplary grades in May 1896.