Next to tracing our ancestors, finding our ancestors’ children must be the hardest thing a genealogy researcher can be faced with. There is no shortage of records that will often point us in the right direction as to who our ancestors’ parents were, and their parents before them, and so on – but finding sources that will actually list our ancestors’ children all at once is slightly trickier.

There are two obvious sources we can use to try to solve this problem: wills, which will often mention the children of the testator by name, and census returns, which again will individually list your ancestors’ children. But genealogical research isn’t as straight-forward as we’d sometimes like: neither of these sources offer any guarantees to discover all of our ancestors’ progeny. For instance, if the ancestor who made his/her will did not want all of their children to inherit their money and property, they may have literally left one or several of their own issue out of the will deliberately. And of course, census returns should – ordinarily – only list children living with the parents at the time the census was taken. Any children who were absent or may have died previously should not be recorded on the census.

If you’re fortunate enough to own a family bible, then chances are you will also have a full list of children born to a specific couple in your family tree. And even then, try to locate supporting documentary evidence to back up all your findings!

But let’s face it: most of the time, finding those missing children in your family history will require patience and step-by-step research. First you’ll have to find a set of parents, hopefully locating the mother’s maiden name in the process, and thereafter see if you can pin-point all the children they had by combining census returns, BMD indexes, baptismal records, and so on.

Genealogy is often compared to a jigsaw puzzle, and indeed, the analogy is easily made. However, there are two essential differences between researching your family tree and the well-known board game that keeps us all amused on rainy days: unlike jigsaws, genealogy will not provide you with a preview of the end result, and therefore you will not be able to tell which pieces are missing until you actually find them; secondly, it’s fairly easy to tell when a jigsaw is complete – you’ll literally see the full picture. Not so with family tree research, which will go on and on as far as you’re willing to take it (why would anyone want to stop at one’s direct ancestors when you can explore multiple collateral branches!).

I was recently pondering on a little tip I’ve used for years when looking for my ancestors’ children, especially whenever I visit archives or have full access to online baptismal records – only now I’ve decided to start implementing it with every single couple that I unearth in my research: calculating how much time passed between the birth of one child and the next. Silly? Obvious? Time-consuming? Perhaps, but you’ll find it’s incredibly effective.

King George III and his wife, Queen Charlotte, had 15 children over a 21 year-period. Source.

Years ago, when I was still living in Spain, I became obsessed with my maternal great-great-great-great-great-grandfather’s family. He and his wife had a staggering eleven children! I was fascinated to find many legal documents which revealed a huge family row that resulted in my ancestor throwing most of his surviving progeny out of the family home. (Yes, he wasn’t a very nice guy.) But what struck me most was that one of these records revealed the name of another daughter I had no previous knowledge of.

In the past I had combed the pages of baptismal records to the point where I had memorised the dates of birth, and yet I seemed to have missed one of their many children. Unable to visit the archives in person, I asked someone to look up a possible baptism for the missing daughter. Knowing when to look for the baptism proved key: the parents had married in 1787, and almost immediately they started churning out children: the first son was born a mere two months after the wedding, followed by more boys and girls in February 1788, August 1789, August 1791, January 1793, February 1794, July 1795, August 1796, September 1797, November 1798 and March 1800.

Assuming that all eleven babies were born at full term, I was able to learn that there had only been a space of two or three months between the birth of one child and the presumed conception of its next sibling. But I knew that one additional daughter was missing, one who could have only been born between two of the others (assuming she was born in wedlock and before the last sibling). I basically needed to find a gap of at least 19 months (9 for the girl’s conception and pregnancy and 9 for the next pregnancy to develop, plus some weeks for what is known as “birth spacing“) and there was only one possible “slot” that could fit the bill: between August 1789 and August 1791. That was the time-frame I asked the research to focus on, and sure enough, in a matter of minutes we found the daughter’s baptism in August 1790!

By calculating the estimated period that each pregnancy usually lasts, and by giving the mother a few weeks or months to recover from her  previous pregnancy, we can make very educated guesses at when she may have given birth to additional children.

Obviously, not everyone had children every year, not every pregnancy lasted nine months, and not every birth or baptism was recorded. Miscarriages, stillbirths and abortions may not have necessarily left a paper trail for you to research, so occasionally you might need to assume that, where there’s a considerable gap between the birth of two siblings, an additional pregnancy may have taken place.

One final word of caution: don’t assume that a break between births necessarily means the premature death of a child or a mysterious pregnancy yet to be revealed. That same ancestor I spoke about before – the one with the eleven… sorry, twelve, children- had a son who married in 1823, and he and his wife had three daughters in quick succession (1823, 1825 and 1827), but the next child was born seven years later, in 1834, being followed by five more children in subsequent years. Of course I asked myself why there was a seven year-gap between the birth of the third and fourth child, especially considering that the couple were obviously still in their child-bearing years, and very much sexually active by the look of things! Well, additional research revealed that the father, who it turns out was politically active, actually spent a certain amount of time living in exile, first in different places throughout Spain, and later in neighbouring Portugal, where he was later informed that the Crown had pardoned him, and he was finally allowed to return to Spain – and to his wife, with whom he resumed his happy and fruitful marital life!

To conclude, remember to include previously-unknown pregnancies when looking for the children your female ancestors may have had, and consider both biological as well as historical reasons that may explain otherwise inexplicable gaps between births. I’m fairly certain you’ll unearth some pretty amazing stories in the meantime! Happy hunting!