Perhaps you could clarify the question. Are you looking for people who are relatives of William Heron? Descendants?
Also, are you sure he died in Toronto, and not near Toronto? Do you have an approximate date of emigration? Perhaps a profession (in case he appears in the Toronto City Directories, many of which have been digitized and are available online through the Toronto Reference Library website.)
Not accounting for enumerator and transcriber errors there are only 6 William Herons and 1 Thomas William Heron residing in the Toronto/York census area in the 1911 Census of Canada none of whom have a birth of 1891.
The 1921 Census of Canada has not yet been released by Library and Archives Canada but should be out sometime soon.
