Lost Man's Lane by Anna Katharine Green

The shock of these words -- if false, most horrible; if true, still more horrible -- threw us all aback and made even Mr. Gryce's features assume an aspect quite uncommon to them.

"Your mother's grave?" said he, looking from her to Loreen with very evident doubt. "I thought your mother died seven or more years ago, and this grave has been dug within three days."