The Man With Two Graves

The Russian Royal Family were all murdered in a cellar by the Bolsheviks in 1918, and for several years afterwards imposters tried to convince the world they had survived.

Suppose there was a member of the Romanov family who did not die in the cellar?

He was already dead, as was everyone who knew he existed, but not before he had fathered a son, and this remained a secret for over 90 years, until an English schoolmaster discovered the grave of a child bearing the same name and date of birth as his grandfather.