For years I've known that my grandfather's brother Arpad Seidner born 1898 in Budapest immigrated to Australia and settled in Sydney with his wife Helen/Ilona after World War II. I've located many records in his native Hungary, and more recently in the Sydney, Australia area, that formed a trail of his whereabouts. Thanks to help I got from a person in the Jewish Genealogy group on Facebook, I uncovered the story of his arrival in Australia, his ill-fated bakery business in Sydney, his divorce from his wife, her burial in 1961, and Arpad's address in electoral rolls up until 1972. Then....nothing. Arpad's own death records were nowhere to be found in Australia nor in Hungary where I thought he might have returned. I also had good help from someone in Hungary verifying Arpad's information and family prior and post immigration since so many people were named alike. He and wife Helen had a daughter but I don't know her given nor her married name so I know nothing about her except what she looked like in the 1950s through the photograph below.
I've searched for his death record in Ancestry, Family Search, JewishGen, and Geni. My Heritage also. Is this the end of the line? Are there rocks under which I have not searched?
Below: Arpad at left with a cousin next to him. Wife Helen sitting down with daughter bending and son-in-law at right.
Thanks in advance for any tips.