It may seem morbid, but disease and death are an important part of the research associated with our ancestors’ lives. In previous posts I’ve mentioned ancestors whose lives were cut short by diseases such as cholera, smallpox, tuberculosis, typhus and maternal mortality (the mother not surviving childbirth). For this post I’ll focus on one of the more consistently common causes of death in early New France (Quebec), infant mortality (including stillbirths and miscarriages).
According to the French-Canadian Genealogist, “Infant mortality refers to the death of a baby before its first birthday. Like his or her mother, a newborn faced a high risk of mortality during, and soon after, childbirth. Infant mortality in New France was significant. According to demographers, the rate of infant mortality before 1680 in the colony was 171 in 1000. From 1700 to 1730, it was 242 in 1000. [By comparison, the 2019 infant mortality rate in Canada was about 4.2 deaths per 1,000 live births.] At least one child out of four died before the age of one, of which 2-4% were stillborn or died during childbirth.1
In an article titled Childhood is a Dangerous Time the author stated, “It has been estimated that a quarter of all infants in 18th century New France failed to make it to their first birthday and that nearly half died before they were 10 years old. Matters were no better a century later: mid-19th century Montreal witnessed infant mortality rates of 250 per thousand live births.2”
That a baby survived birth was no guarantee that they were no longer at risk of dying. Mothers that did not or could not breast feed, were unable to pass along immunity that the milk provided, while unsanitary conditions involving hands or utensils passed along pathogens to unprotected infants.
Mothers in early New France had many jobs: they tended to the children, the household, the garden and the animals. This meant that infants might be left unattended or in the care of their siblings, who were also children. Unfortunately, accidents happened. It was also common practice for mothers to sleep with their newborn babies, which sometimes ended in the baby being smothered.
Some of these causes of death still occur today. However, because of childcare education and medical advancements, the associated survival rate both pre- and post-childbirth are nowhere near the numbers seen in the 15th through 19th centuries.

In the article Childhood is a Dangerous Time the author posed an interesting question regarding the high infant mortality rate. He asked, “What were the implications of such a high death rate for relationships and the experience of childhood? Some historians have taken the view that the high incidence of infant death (along with stillbirths and miscarriages) impacted the development of strong emotional bonds between parents and children. As one study claims, Parents resisted making large emotional investments in their children until they demonstrated their ability to survive. The delay in naming infants and the practice of giving the name of a child who had died to a subsequent child are cited as practices which demonstrate this relative lack of attachment. Thus, a situation of high infant mortality is in a sense a vicious circle, with children valued less because they are less likely to survive, and with the lower emotional investment in children reducing their survival chances.3”
This is the first time I read about the practice of giving the name of a child who had died to a subsequent child (there are many instances of this occurring in our family). They state “relative lack of attachment” as a reason. I thought it was maybe to honor or remember the child that had died. I’ve always wondered how our relatives emotionally survived the deaths they witnessed and how it shaped who they became. I have a hard time believing that they were so emotionally detached.
My first brush with a high infant mortality rate related to a direct ancestor happened when I stumbled across the fact that my great-great grandparents, Francois and Tharsile (Hus-Lemoine) Vadnais had more than 4 children. It started with my questioning their being married in 1848 and the first of these 4 known children not being born until 1858. Ten years between marriage and the first child being born is unheard of in most French-Canadian Catholic families. As a result, I ended up looking page by page through the church records across those 10 years.
What I found was 4 more children: Marie Celina, Marie, Timothe and Francois. Marie Celina, Marie’s twin, died the day after she was born.4 Marie lived for about 2 weeks before she passed away.5 Timothe lived a little over 2 years before dying and Francois lived 3 days.6 The deaths of Marie Celina, Marie and Francois are all considered infant mortality while Timothe’s death is considered childhood mortality. You can read the details about Marie Celina and Marie here and about Timothe and Francois here.
More recently I found another ancestor that suffered the loss of a number of children to infant mortality. This particular relative, on the Peltier side of the family, was my 2nd great-grandfather Charles Joseph Peltier’s youngest sister Henriette, my great-grandaunt. Henriette Peltier was born in 1829 in Quebec and lived out her life in the Joliette, Quebec area where she was born.7 In 1848, at 19 years old, she married 25 year old Louis Valois.8 Their first child, Louis Valois was born in June 1849 and their second child, Joseph Adolphe Valois was born in August 1850. Both would marry, have children and live long lives.
What happened to Henriette’s subsequent children is nothing short of mind-boggling. From 1851 to 1860, Henriette gave birth to another 11 children; none of them survived. Only one was identified as female with the gender of the others being unknown. None of the children were given names, but for a few of them vague information about their death was recorded.
The first child, Anonyme (Anonymous) Valois was born and died on August 24, 1851. The writer wrote she died a few moments after being born.
The second child, Anonyme (Anonymous) Valois was born and died on March 16, 1852.
The third child, Anonyme (Anonymous) Valois was born and died on April 4, 1853.
The fourth child, Anonyme (Anonymous) Valois was born and died on February 2, 1854.
For babies 5 through 11, the writer wrote anonymous child born and deceased.
The fifth child, Anonyme (Anonymous) Valois was born and died on May 15, 1855.
The sixth child, Anonyme (Anonymous) Valois was born and died on December 30, 1855.
The seventh child, Anonyme (Anonymous) Valois was born and died on January 17, 1857.
The eighth child, Anonyme (Anonymous) Valois was born and died on July 27, 1857.
The ninth child, Anonyme (Anonymous) Valois was born and died on September 11, 1858.
The tenth child, Anonyme (Anonymous) Valois was born and died on April 5, 1859.
The eleventh child, Anonyme (Anonymous) Valois was born and died on May 22, 1860.

Henriette was 31 years old when she gave birth to her 13th, and last, child.
As I said before, I found the loss of Henriette’s 11 children mind-boggling. I talked with a few people about it and we wondered if her babies had Rh-factor, a condition where a protein on red blood cells can cause problems, specifically, Rh incompatibility, for pregnant women and their fetuses when the woman is Rh-negative, the father Rh-positive and the fetus is Rh-positive. The condition may lead the mother’s immune system to produce antibodies that attack the baby’s red blood cells. Sadly, the associated problems will tend to get worse with each Rh-positive pregnancy.
It would not be until the 1940s before the Rh-factor would be discovered. As a result of the discovery, mothers are tested and treated to ensure their children will survive.
I am very thankful for all of the medical advancements that have occurred to date. I can only imagine that Henriette and Louis would have done anything they could if they had known what was killing their babies. Although we will never know exactly what happened to Henriette’s 11 children, this case does speak to the importance of looking at disease and death in genealogy research. If nothing else, it provides us with a perspective on a period of time and it forces us to think about some of life’s toughest challenges.
Thanks for visiting, come back soon,
Cynthia
© 2025 Copyright by Cynthia Vadnais, All Rights Reserved
Footnotes Infant mortality among our French-Canadian Ancestors post

This was very interesting. The RH factor played a part in my first pregnancy with son, John. He ended up not needing a full transfusion.
oxoxo
How sad.
5 children’s gravestones at St. Mary’s of the Lake for Rosemarie Derosier’s children. Deaths 1900-1909. Oldest was 12. Maybe other infant mortalities?
Thanks for this realistic visit to family history.