Your complex evil characters might want to avenge, well, nearly anything. And even if you used that as their motivation before, it doesn't mean you can't use it again. It can still work.
Of course these days only women and transmen give birth (although medical science may change that someday!). However, anyone can always witness it, not only the actual event but also everything leading up to it. And don't forget about how it can even be a bitter fight as to who gets to be in the delivery room. Mothers in law, I am looking at you.
If your southern American characters sound like Gomer Pyle, and your Mexican characters sound like Señor Wences, you are probably not doing such a hot job with depicting their accents. Same with a British character who ends up sounding like Dick Van Dyke in Mary Poppins. Just, don't.
When Jewish characters (for example) are on the screen, does the audience get more than an occasion reference to Chanukah? Or do they just get a surname, or a trope? Or worse, do they get thinly-veiled anti-Semitic caricatures? Are LGBTQ characters defined by their sexuality, or are they stereotyped, or is it no big deal? Or are they killed off quickly, once they're no longer useful to the plot, the show runners, or the network?
Yet another thing to think about concerns the making of films. When films open, they are huge collaborative efforts which include not only the writers, actors, makeup and set people, special effects, the director, and the producer. They are also a product of budgets, and of timing. When a tragedy occurs, a film might be delayed, or even shelved indefinitely. And the same thing can happen if the star dies or becomes embroiled in a scandal. Furthermore, some films would benefit from an update in special effects technology. And others would change with our current social sensibilities regarding feminism, LGBTQ rights, and other issues.
What happens at the top of the ticket? And that doesn't have to just be in America. What about in other countries? How are leaders chosen—and who do they end up beholden to when elected? Top candidacies get a lot of press, and national leaders have nearly no time to themselves. Even bad leaders can be inundated with work. These are undoubtedly extremely stressful jobs, no matter the size of the country or the type of government.
Widows and widowers may, consciously or unconsciously (and not necessarily fairly) compare their dearly departed with any potential new lovers to come down the pike. And conflicts can arise from everything from putting old pictures away—and taking them off the walls—to taking off the wedding ring.