You wrote: [was from the First Nations. Ezilia Marguerite Breault was the daughter of Arthur Breault, born in Normandie, France, date unknown, and Salome Hillde Brown, born in Malone, NY, approximately 1856. Arthur Breault and Salome Hillde Brown died in Valleyfield,Quebec, in 1926.]
Have you found a copy of Arthur's death certificate or a photocopy of Arthur's burial act in the church register ? If not, ask for it. It might contain the names of his parents.