Sarah, don't know if any of this will help you, but here's some background on what was happening in Canada between 1830-1850.
A couple of years ago, I was fortunate enough to speak at length with Prof. Andre Senecal from the University of Vermont dept of History.We specifically discussed this very time period and how long established families suddenly dispersed in all directions...with so many ending up in the US.
From what he told me, the economy in Canada...and especially Quebec...got very dismal.There was difficulty feeding people, jobs grew scarce, rebellions hit in 1837 and tensions with the "First Nations" made things a little precarious.Ontario and Quebec didn't unify as it were until 1840, so there was no greater incentive for the early emigrants to move into Ontario than into the US territories.
To avoid starvation and unemployment, families picked up and jumped across the border into Vermont and upstate NY, Michigan, and Wisconsin, where the young lumber industry promised housing, food and jobs. Those who stayed in Canada often moved west into Ontario and settled in the peninsula that juts down along Lake Huron and Lake Erie, joining the fishing, fur and trade industries.My own line of Tessiers even got into smuggling runaway southern slaves into Canada as the last leg of the Underground Railroad.
If you can get as far back as Michel's parents, the odds are great that you can quickly and easily complete the rest of the tree.
If Michel ended up in the Lake Erie coastal area and was a Tessier...Tacey...Tasey...in the beginning, then the odds are decent that you'll find a birth record on him in French Canada if you can identify the pockets where Tessier descendents lived between 1800-1830.Ste-Elisabeth, Joliette is one place to look, and I'm sure that Reg and others can give you other ideas.