The family of John W. Heck appears in the the 1901 Census for Middlesex South, district d-8. It includes his son John and daughter Charlotte, and daughter Bertha Boyd and her husband Robert and children Myrtle and Francis.Olive Tree Answer: Diane, it sounds like you've done a lot of good research on your Heck family. Thank you for providing such a detailed account so that I could try to help.
Another daughter,Sarah Jane, and her husband Richard Weir, who were married in 1887 in North Oxford County, Ont., appear in the 1910 census for San Bernardino, California, ward 3. In the 1920 census they say that they moved to California in 1887 and were naturalized in 1894. Richard seems to have been in California since 1883.
I can't locate Bertha and Robert Boyd again until the 1920 California census for Los Angeles, where the naturalisation date for Robert is 1875.Also in 1920, the younger John Heck is living with his sister Charlotte and her husband Benjamin Uglow in Long Beach, California. Charlotte and John say they came to the US in 1906.I'm wondering if everyone else in the family, other than the Weirs, came at the same time.
Also, when did John Heck Senior die in Ontario? Did the Boyds and Charlotte wait until his death to emigrate? I have not found his death record on Ancestry.ca. I found the American census info on Heritage Quest on-line.
I see you have some naturalization years for some of the family. Have you looked for naturalization records? They may provide you with more clues. Be cautious though, because the year of naturalization was one of the most MIS-remembered dates of all! So allow a year or two on either side of any dates given in the American census.
It looks like some of your family left Canada for USA before the Border Crossing records began in 1895 but if Charlotte and John arrived in 1906 they might be on the lists. However, before 1906 Canadians were not noted, so they may have missed being recorded! It is worth a look if you have not checked those border crossings.
I would also track every branch of the families - search for obituaries of every descendant in hopes of finding a little clue. Did you consider the possibility that they may have used various names? What I mean by that is that quite often an individual might use his first or his middle name interchangeably. So you will want to search by middle names as well as first.
The death record of Robert Grant Heck in 1926 found online in Family Search's Ontario Deaths 1869-1947 shows that his father's name was John Wesley Heck (mother Elizabeth Purdy). Perhaps he sometimes went by Wesley rather than John. Or by his initials J.W. You will want to search under all possible variations of the name(s).