I came across an old newspaper story (Free Press Home Journal ,January 4, 1900) that may be connected to the Monchalin family. It involves Rosine Monchalin who married Mr. Denzer. As you found in the Vital Statistics site there is a marriage for Rosnie Monchalin and Pierre Deutzer on December 12, 1898 in the rural municipality of Lorne. There is also a birth for Marie Josephine Rosalie Dentzer on November 12, 1899 in the rural municipality of Lorne. If you click on details you will see the mother is Rosalie Monchalin. Because of the newspaper story I believe the two deaths involving Rovimain Deutzer who died on December 22, 1899 in the RM of Lorne at age 24 and Pierre Deutzer who died on December 25, 1899 in the RM of Lorne at age 38 to be the same Rosine and Mr. Denzer. I know there seem to be various spellings.
The story is not a happy one. Would you like me to post it here?
Karen in Winnipeg