Send a message to the person who requested a photo of the grave monument of Jemima Wharton Duff with the following comment:
To check an apparently incorrect date of death for Jemima Wharton Duff in another website. (N.B. I and others are currently photographing gravestones in my local churchyard. I would like to think that we can add them to your database but I have yet to discuss this with the others involved in our project.)