Hi Just found your message to.day
Doing my own research last year I found the following deaths. All buried in Cookstown, Co Tyrone
Frederick Ludvoig Von Stieglitz Aged 63 Died 18 May 1866, From Newry
John Von Stieglitz,died 25 August 1868, from Rostrevor
Robert Von Stieglitz,aged 59,died 22 March 1876,from Kilkeel.
Hope this of interest to you,any more detail just ask