Cynthia was born to Silas M. Parker and Lucy Parker (née Duty) in Crawford County, Illinois. Her birth date is uncertain; according to the 1870 census of Anderson County, Texas, she was born in 1824 or 1825. Originally, her middle name was Ana, but over the years, her name was changed to Ann. When she was nine or ten years old, her grandfather, John Parker, was recruited to settle his family in north-central Texas; he was to establish a settlement fortified against Comanche raids, which had been devastating to the Euro-American colonization of Texas and northern Mexico. The Parker family, its extended kin, and surrounding families established fortified blockhouses and a central citadel—later called Fort Parker—on the headwaters of the Navasota River in what is now Limestone County.