Hi Carla
I presume you are familiar with the origins of the name John Baptiste.
If not check out
http://en.wikipedia.org/wiki/Jean-Baptiste.
It would be easy to make the change from a father christened Jean-Baptiste married to a woman of English parentage to a son named after the father as John Baptiste. What is missing is the surname.
To solve the problem you need geography, a low population density, and a little luck on you side.
When I looked at your Baptiste/ Battis/Battist names I had hoped to find some locations so you will have to look in your tree for the earliest possible location.
I would start with John Battist married to Mary Eliza Turner 24 May 1848. Here you have very recognisable set of childens names with most of their birth years. This is just the sort of group you can identify in the Canadian census returns. You may have done this already since this is one of the most common ways of identifying birtth year data. With any luck you will find residence and birthplace location recorded in the census.
For information on census index holders go to :-
http://www.collectionscanada.gc.ca/genealogy/022-911.009-e.html
One thing which is obvious is the date of the marriage. If known exactly then the location is also probably known. This should narrow down the census search area.
Once you have birth location information and age of John Battist you may be able to work back through census returns to John Baptiste. This is where you need a little luck because you may only have the fathers Christian name Jean-Baptiste and you will have to start using wild cards in the search engines for surnames in census returns. Low population density may come to your rescue here because you are now searching for a Jean-Baptiste (christian name) married to an English woman with a son called John, at the location of his birth, in a census return before 24 May 1848. With a following wind you may now have the original French surname and can start digging back into immigration and passenger list information. You may find that there are a whole series of father/son christian namings as Jean-Baptiste to help you on your way. They are most likely to be first born sons.
Regards
John Shipton
Devon, England