I will reply in English in order to help anyone who might be looking for the same information.
I don't have much data, actually. All I know is Eugène's parents were Dosithe Bérard and Mathilde Deguire Desrosiers (or Deguire dit Desrosiers), both from the Saint-Nazaire area in Quebec. Eugène's wife was Ozéline Boisjoly. Our first anscestor to come to Quebec in 1670 was probably indeed Gabriel Bérard dit Lépine (born in 1644), but there are still quite many missing links!
I'll look forward to reading more details as you find them. As for me, I put my father (André Bérard) on this dossier, and he's good at finding this kind of information.