Etienne St. Aubin from Quebec to St. George IL 1800s

Etienne St. Aubin married Philomene Boudreau in 1861, St. George, Kankakee county IL. Both were born in Quebec Province (1838 & 1841), but I don't know where. Etienne died 1900 & Phiomene died 1924. I believe Etienne's father was Jean Baptiste, born 1797 in Canada and died in St.George in 1870. I just can't seem to find anything else. Most of the St. Aubins in on-line info sites are from the Michigan area, and they seem to have the "dit Casse" name.
1. Who were Etienne's parents?
2. Grandparents?
3. When did they come to Illinois?
Thank you for any information you can provide.