Families have always been the most basic unit of social organization, which is one reason we are now so exposed to disorder. Families have always been in tension several ways: between love (for partner, children and extended family) and sex (simple conjugation, lust) because "tension" comes from contradiction and the struggle for either reconciliation or finding a way to avoid trouble.
Also, tension abides between the individual (often lust but possibly love) and the community (same). The need for reconciliation is what creates narrative, because all of these are time-arts -- or time-sciences. One thing triggers another. Each small thing is part of the story.
Given this, one answer that develops in every culture is that of established boundaries of behavior. In some situations, more reproduction is most important. In another, it is the support of the new person who arrives. In one situation it is important NOT to have a child -- in another one is pressed by economics or something else (what?) to have a child.
Cultures are created by genomics pressed against environment: we do what will let us survive -- or we don't. Because of human memory and imagination, it is possible to defend one's identity even when out of step or disobedient enough to be killed, and then the identity goes on in story. Or it can go the other way, so the community erases your identity, but you go on living. Stories like The Handmaid's Tale" make a whole group one's identity for the sake of the community.
When I was raised, during and directly after WWII, the rules were very clear and conveyed to me in the strongest terms. Do not get pregnant. If you are married, you must get pregnant by your legal spouse. If you do get pregnant out of wedlock, you must bear the child but then you must give it away and keep the whole thing secret. If the child is faulty, best to let it die. If it is born dead or dies shortly after, best to deny it ever existed.
Ignore all feelings of your body or desire for well-being because your "job" in life is to fulfill these rules for everyone's sake.
An alternative is to live through a man but outside marriage, or through men as a whore. Whoring is not about the use of the body but about not being human anymore, an economic necessity. But there are higher forms of using the body this way if you can find them. Do not have children.
Same sex people can explore this option more easily than hetero couples but the price -- as always when crossing a border -- is secrecy. A boundary which in one culture will simply get one killed and is a sharp line, can become a rather wide country where a person can dwell. It has a double-boundary, one when you cross into the forbidden and one when you go further to the unforgivable.
Much of this is situational. You'll find out through consequences and watching the others, because there will be others.
But the world changes. Legal abortion and effective contraception have changed the rules, which the gerrymanderers do not like, so they try to force old consequences to return. They will go so far as murder. That's another legal border that wavers, thins and thickens.
Legality is always in competition or collusion with natural consequences. The laws on marriage are disregarded by many and ignored in complexity by those who blindly marry or divorce. These laws are the work of the States and the reservations, which are quasi states. Paperwork like "licenses" (which are sometimes presented as permissions that preserve legality) for birth, marriage, and death are meant to manage "ownership" of property and "responsibility" for children. They are monetary matters, but also useful in managing propriety, acceptable to conventions.
Some legality can be taken to one of several kinds of court: the Rule of Law, which is written down but still negotiable; or tort law, which is about matters that must be argued; or delineated by the context like marine law or tax law. Law on a reservation is likely to contain fossils from earlier and offensive times.
How are we to understand how to frame up new principles and Rules of Law for today's living ways. We want survival for individuals, but can we find and enforce that edge? Some communities find their lives so impossible that they become emigrants and disrupt the new places that they are considered immigrants. Though they are individuals, they become a group.
Two social forces try to manage groups with rules and sometimes force that may be secret. One is the government and the other is religious. When conservative "Christians" were numerous enough to make the US act like a theocracy (the two forces merged), the rules were in one place but now there is too much variety.
One of the purposes of family and many mechanisms of the whole (school, church) is to make constructive adults out of children. With so much chaos, both economic and cultural, this isn't happening. We are stockpiling children in warehouses not equipped for making children human, much less adult. They do their best by helping each other but it is not enough. They age quickly and as they age they changing voting. So it is noted that many of the people who voted for Brexit are dead. (The old are likely to want to preserve the past.) But many of the people who have come of age since the last vote are now old enough and much more oriented to a future with Europe. This does not usually work in favor of the conservatives.
What principles must we make real? Individuals must not be invaded or forced. Communities must find ways towards unity -- something besides opposing others. Many boundaries will have to be erased. Others need to be invented. "Escape" alternatives need to be arranged. A grand and embracing narrative about what it is to be human, what it is to live on a planet like this one even if it changes, and what to do with a new infant, both inside while gestating and outside learning to walk and talk, building an inner architecture of hope and laughter.