They had at least three sons, Edward Dwinnell born in 1882, Richard John Walter Dwinnell, born in 1884 and Lorne Nelson Dwinnel, born in 1884.
In the 1887 city directory David was a steam fitter.
1887 Montréal City Directory Listing
In The Brockville Evening Recorder on August 15, 1900, the social column reported that a Mrs. D. L. Dwinnell and her son of Montréal were visiting her brother M. J. Connolly of Caintown.
The U. S. Patent Office has several patents listed in 1890 for David L. Dwinnell including a fitting for hot-water and steam pipe, hot-water boilers and , a closet cistern (page 2).
In the 1894 city directory David was an inventor.
1894 Montréal City Directory Listing
At the time of the 1911 census, the family was living in Montréal, Québec in the Maisonneuve district at 1326 St. Andrew. The household consisted of David Dwinnell born in December, 1851, Maria Dwinnell born in 1847, Richard Dwinnell born in January, 1884 and Lame (sic) N. Dwinnell born in October, 1884.
Yonge Mills, Ontario was in Front of Yonge Township near Brockville. It is north east of Kingston and north of Watertown, New York. It is now a ghost town. In the mid 19th century, Yonge Mills, was a busy and prosperous village with a population of about 175. It had a sawmill and a fulling mill. There were hotels with taverns and a general store. The village also included two blacksmiths and a church.
The peak period of Irish immigration to Canada was during the Great Famine between 1845-1849. Most immigrants went to Canada because the fares were lower. Ships that reached Canada lost many passengers and even more died while in quarantine. From the reception station at Grosse-Ile, most survivors were sent to Montréal. The typhus outbreak of 1847 and 1848 killed many of the new immigrants. An economic boom following their arrival allowed many men to work in on the expanding railroad, in construction, in the logging industry, or on farms.