I have four nieces and a nephew, none of whom I get to see very often as they all have young children.
Last Christmas, Niece 3 invited my partner and me to her house the morning before we traveled home. I engaged her husband in a little banter, whereupon he exploded that we shouldn't have come over without calling ahead. Feeling quite unwelcome, we left, despite my niece's protestations that we were always welcome in her home.
Her husband has never apologized to us. This has clouded my relationship with my niece. This year's visit is coming up, and I would appreciate your suggestions as to how I should handle it.
Answer: That's one answer to one possible interpretation - that the husband is a volatile jerk who doesn't want you in his home.
But since this spousal eruption was apparently a first, the possibility of other interpretations remains: including, say, that he and Niece 3 had been arguing when you arrived, and he lacks the social skill to have handled his distress more smoothly. Or, something else explains it, something that had nothing to do with you, but he lacks the social skill to recognize that his duty to apologize trumps his impulse to hide in shame.
Maybe he really is explosive, and you witnessed one point on an otherwise-unseen continuum. In that case, distancing yourself from Niece 3 would compound the problem. If he's trouble, then she and her kids are in trouble. And while helping someone in trouble is complicated business, the simplest part is staying in nonjudgmental touch.
So, do accept any invitation your niece extends, open your minds, and see what happens. Just call before you show up.