How do I write about a character’s strictly homosexual grandparent born in the 1910s? That would mean that they had to have straight sex and an unhappy coerced marriage to fit in in order to have children since there is pretty much no way they could have adopted or had ivf or surrogates back then. Unless I make both grandparents are strictly homosexual and didn’t actually have sex to make children, but that is still fitting in...??
Adoption did actually exist then!
It’s existed throughout history.
The formalities of it have varied, however, as well as the reasons one might adopt. But adoption has always been an option. I would almost argue that it was easier to adopt in the past as things had less paperwork and vetting, even going so far as circumstances where children were taken from their parents without parents knowing they were safe. (This still happens today of course, especially with racialized kids. The foster care system needs a lot more care involved and needs to be abolished for some communities with pre-existing cultural systems for dealing with childcare and such.)
You might also look into the concept of “foundlings” which were children who were abandoned and taken in by others. This is the term for the “doorstep children” you often hear about in historical and fantasy settings. It doesn’t happen so much now, as generally these circumstances are much easier to investigate with DNA testing, security cameras, more thorough witness tracking and interviews, and so on, and parents who do this can be found and prosecuted for child abandonment. But it has happened a lot, all throughout history, especially in communities and societies that stigmatized pregnancy and children born out of wedlock.
Regarding your question, I would just suggest having it be an adoption scenario.
You could also have a trans or intersex parent. (If you do have an intersex parent, I would look into the different intersex conditions and pick one specifically that would work in this circumstance, because they are not interchangeable.)
I also want to add this, but to be super clear, I want to clarify that this is not intended as a callout or correction. I just figure if you don’t already have this info, it might be a good supplement for information regarding terminology and historical realism.
I figure maybe you might know this part, but in the interest of just-in-case, and because it was worded this way in the question, I want to add this info. The term homosexual, while more commonly used in the past (including the era you’re writing about), is a clinical term for an antiquated diagnosis that is generally pejorative these days, in the English language anyway. At the time frame that you are describing, in most of the English speaking world, while homosexual was still used, there were still other phrases and slang and whatnot that people used. One of the terms was “similisexual” (link is to a book on WikiSource published in 1910 using this word) and there were several others too.
Especially with stigma and criminalization, people found language to use to allude to who they were and talk in language only each other could understand. (Polari, etc.) I might suggest doing some research into the variety of language used at the time to at least add some variety and a nod to the folks who are very uncomfortable with the term homosexual. Not everyone is of course, and some people prefer it. But it’s worth it to mix it up.
Also, tangentially, but another thing, it’s not necessarily straight sex especially if no one involved is straight. That’s one of those things where the people involved get to define it. (So you as a writer would, with your characters, but you don’t need to keep it uniform if you feel like your characters might feel differently about it.)
Thank you for asking this stuff!