“…Local legend says that the children of a doctor who once owned the [Highgate Manor] and performed experiments on them have remained in the house since they died.[2]…
Dr. Henry Baxter…opened his practice in the manor, where there are still blood stains on the floor in what is now the library. It is believed that he performed experiments on his children, most of which did not live past the age of ten.[2]…”-https://en.m.wikipedia.org/wiki/Highgate_Manor
The featured image shows some of the graves of Dr. Baxter’s supposed victims: his children.