William St. Denis died date unknown.He married Modeste Seguin-Laderoute on 25 August 1891 in Rigaud, Vaudreuil, Quebec, Canada, daughter of Cyprien Seguin-Laderoute and Marie-Catherine Mallet. More About William St. Denis and Modeste Seguin-Laderoute: Marriage: 25 August 1891, Rigaud, Vaudreuil, Quebec, Canada.