Go to www.fultonhistory.com
and search in quotes
Several articles about the incident.
The only census I seem to find Mabel Silvernail in is the NYS-1892 Census where she is listed
John L Silvernail 25
Mable Silvernail 14
Maranda Covert 77
If she is 14 in 1892 she should have been born about 1878. She is not on the 1880 Census with Seymour and Caroline. Of course, the 1892 census could be wrong
Her mother was involved with Frank Angel-maybe he fathered her???
South Bradford Cemetery
Silvernail S B 1813-1880
Silvernail Caroline 1850-1894
Do you have any dates for Mabel??