It’s hard to talk about kinship without also talking about marriage, but I’m going to delay that for the time being, and stop on the border between the two by talking about residence patterns: where people live, and with whom.
This topic is at the forefront of my mind right now because as I type this, I’m in Massachusetts, visiting my husband’s family for Christmas. We live in California, clear on the other side of the continent from them. My own parents live in Texas. This is relatively common in the twenty-first century United States, but in the grand scheme of things it’s kind of weird. Historically speaking, and in many parts of the world today, people tend to live much closer to their family — one part of it or another.
The term for what my husband and I have done is neolocal residence. When we got married, we lived in Indiana (where I was attending grad school), nowhere near either his family or mine: in a new place, hence “neolocal.” As with lineage, it usually skews toward either the male or the female. When a couple lives with or near the husband’s side of the family, it’s called patrilocal or virilocal residence; when it’s the wife’s side instead, that’s matrilocal or uxorilocal residence. (The former term applies if it’s the whole lineage you’re staying near, the latter if it’s just the immediate family.)
Who you live near isn’t just a matter of chance or trivia. Staying near your own kin means that you remain an insider, and have your family around you as a source of support. Going to a new place means leaving behind your own networks, or at least putting them at a much greater remove, and becoming an outsider among strangers. It’s no coincidence that the Chinese government has tried to encourage matrilocal residence; under the patrilocal model, daughters are “lost” to other households and towns, siphoning wealth from the family. As a result, China has an ongoing problem with female children being preferentially aborted, killed in infancy, or abandoned. Encouraging new households to form near the wife’s family might help mitigate that issue.
There are all kinds of social structures around these residence patterns. In uxorilocal cases, sometimes the husband owes “bride service” to his in-laws, working for them (e.g. on a farm) in exchange for his wife. If inheritance is matrilineal, the couple may have what’s called a “visiting marriage,” where the husband and the wife actually live separately: she stays with her own kin and he stays with his, visiting his wife periodically, but mostly being involved with the upbringing of his sister’s children. On the other hand, neolocal residence requires that the couple have enough resources to maintain their own household without assistance from kin, which often interrelates with things like average age of first marriage and the employment situation of both spouses.
Then there’s the question of who’s in the household. I said above that it’s patrilocal or matrilocal if the society is organized such that whole lineages live in proximity to one another, but virilocal (literally, “man placed”) or uxorilocal (”wife placed”) if it’s only the immediate kin. Which brings us to the topic of nuclear vs. extended families.
Most of us here in the U.S. live in nuclear family units, consisting of parents and their (usually immature) children. Sometimes it’s a single-parent home, or sometimes there are step-parents or half-siblings involved, but the general principle of “two generations in one house” is what defines the nuclear family. Extended setups get more complicated: it may be a stem family (grandparents living with one of their children and that person’s spouse, plus grandchildren) or more extended than that, with multiple adult children and their spouses and children remaining with the grandparents.
The power dynamics here can vary widely. Is the eldest male the patriarch, controlling the younger generations of the household? Or have the oldest generation moved in with their children because they need caregiving or financial support themselves? The former is more common when all the sons remain in the household, the latter with stem families or nuclear families that have expanded outward to accommodate the older generation. (That last is increasingly common in the U.S.) And I won’t dive down the rabbit hole of domestic architecture today, but for now, take it as read that how you go about building your house has a lot to do with how many people are expected to live in it, and with what configuration of power.
Humans being what they are, of course, we don’t always stick to these neat little boxes. Polyamorous families, whether informal or connected by law, extend the household in ways that aren’t necessarily generational. Out here in the Bay Area, where housing prices are ludicrously high, I know an increasing number of people who have banded together with unrelated friends in order to afford a mortgage. In eighteenth- and nineteenth-century England and the U.S., the situation of two financially independent women living together was common enough that a term was coined for it: “Boston marriages”. Some of those women were in sexual relationships with each other (and might have gotten formally married if they could have); others simply wished to live without being dependent on a man.
Or take college housing situations. I don’t know if it’s true, but I remember hearing when I was in college that by some old Massachusetts law, any structure housing more than six women and an unrelated man could be considered a brothel; by that definition, every single dorm was a brothel. Mixed-gender co-ops are similar. People may live together for all kinds of reasons, ranging from the financial (”it’s the only way I can afford this”) to the ideological (”I want to be in a community of vegans/queer people/Buddhists/etc.”) to simple convenience.
Many speculative fiction novels, though by no means all, neglect the question of family. But unless your characters are all foundlings, they have or at least had parents, and quite possibly siblings or aunts or cousins, too. Those people are going to live somewhere. Taking a moment to consider where that might be will make the social network of the story feel more real.