From the desk of Stephen White....
Marie-Agnès D'Amours ...
Placide Gaudet identified Marie-Agnès D'Amours as the daughter of Louis D'Amours de Chauffours and Ursuline d'Abbadie de Saint-Castin (Généalogies acadiennes, p. 3902). This identification is very plausible, given that Joseph Roy's sister Geneviève married Marie-Agnès's brother Joseph. In the case of this second couple, the link to Louis and Ursuline is incontestable, because Ursuline is listed with them in various documents, including the 1767 census of Miquelon.
I do not believe that Marie-Agnès's father was the son of Louis D'Amours, however. That boy would have been rather too young to have had children by the mid or late 1710's. Instead, I think Ursuline d'Abbadie de Saint-Castin married the son of Mathieu D'Amours de Freneuse and Louise Guyon who was born about 1689 (DGFA, pp. 6, 458). Some might think that Ursuline's husband had to be Louis's son because of the "de Chauffours" attached to his name, but such seigneurial titles did not always pass from father to son. In this case, I think it is quite likely that the Louis D'Amours who was born in 1698 died young, without issue; I have been unable to find any mention of him after 1707 (DGFA, p. 456). In such circumstances, the "de Chauffours" title would have been kept alive by its adoption by one of the boy's cousins, which I think is what happened here. By coincidence the cousin in question happened to be another Louis, and this other Louis was around seven years older than Ursuline, rather than two years younger. In my opinion it is much more likely that he was the one who continued the lineage than his younger cousin.