re error on death certificate - I made the same error on my own father's certificate many years when unexpectedly asked for my paternal grandfather's name (when I went in somewhat of a rush to register death so that could hold funeral within a very short time as one of my brothers had to return overseas in a day or so and in those days children knew gparents by 'granny smith' etc and would never refer to them by their first names) I mistakenly gave my father's first name - on getting back home I rememembered but too late! I suspect the informant of John's death not knowing John's father (a continent away) recalled that John's son was named after his gfa - thus the Frederick rather the William ?