If we had a time-frame, it would help. I've only been able to find one RODRIGUE DUCHARME (Isidore+Lina AYOTTE) b. & bapt. 1886-03-28 in Saint-Thomas, Joliette County, QC. Godparents: Joseph DUCHARME (son of Isidore) & Eugénie LAVALLÉE (daughter of Éphrem). I'm giving you this info since Rodrigue's middle initial was I so this Rodrigue, son of Isidore, may be a link or the right person IF 1886 is a correct time-frame. I've also found that Isidore DUCHARME+Mélina AYOTTE (same couple as parents of Dodrigue above, had a son names ARTHUR DUCHARMEb. 1883-07-23, bapt. 1883-07-24 in Saint-Thomas, Joliette County, QC. Godparents: Cutbert DUCHARME (son of defunct Isidore) & Hermina BOURRET (daughter of Jérôme). So, since you've mentioned that RODRIGUE had a brother names ARTHUR, the above info may be his birth & baptism. Good luck in your research.