Irish in Nepean Area, Canada

I have been reading about the Irish immigrants in that county, where Daniel Patrick McGill was born.   Nepean's first permanent settler came to the area in 1810. However, it was the building of the RIDEAU CANAL that boosted settlement in the township with many coming about 1825.  The first settlers farmed plots that were given them and worked on the lumber drives in the winter.  It was a heavily forested area but also swampy.  Among the many diseases that ravaged workers during the building of the Rideau Canal, three of the worst were dysentery, small pox and malaria.Not only the workers but their families suffered from these diseases. We do not know if one of these illnesses caused the deaths of Patrick and Mary McGill's two baby girls, or Patrick himself.