Belle Simon was one of ten children born to Rose and Joseph Simon, a successful trader in Lancaster, Pennsylvania, including sister, Miriam. She married Solomon Myers-Cohen, a merchant and shopkeeper from New York, and there they began their family, in the community around Congregation Shearith Israel. The family left for Philadelphia at the start of the Revolutionary War, where Solomon served with the Third Battalion of the Pennsylvania Militia. After the war, they returned to New York—Solomon was named on the earliest post-war tax lists for New York. However, when her husband died, in 1796, Belle took her seven children—the youngest only three years old—and returned to Philadelphia. There she raised her family, including son, Joseph, in the community around Congregation Mikveh Israel.