Alfred Yoon was my great uncle.his sister Katherine was my grandmother.she had a son named Jim van horn.he is my father. the sister who's name you don't remember is or was Betsy. i don't know her married name.our family lives in Indiana. my father Jim van horn is still living.he may be able to help you with any more questions about the Yoon family. uncle Alfred lived with my parents in Indiana for a while after a stroke.he later went to a nursing home because he lost a leg and my mother wasn't physically able to take care of uncle Alfred.he passed away in 1988.