Candice McKnight all but moves mountains to help people find their roots.

But it was on an imposing rock set down in a stranger’s yard in Missouri that she looked her own family’s past in the face.

The president of the African-American Historical and Genealogical Society of Colorado Springs was visiting family when a cousin, who belonged to a historical society there, showed her the rock that had been a platform from which slaves were sold in the early 1800s. Intrigued, they found papers that showed that a great-great-grandmother had been sold there.

But in an unusual twist, the woman was a French indentured servant who was sold to an African-American family,