Quick background: I live in a house with my sibling and their parents. My sibling is not legally or biologically related to me, but they ARE my sibling. My sibling's parents are not my parents, but we are collectively a 'family,' in many senses of the word. I call my sibling's parents "the Elders of Plumley" as Plumley is the name of our house, they are the oldest members of our household, and they are sources of great wisdom. I myself am in my late teens (no longer in high school.) My sibling is in their mid teens (still in high school.) All of us in the household are various hues of neurodivergent. (I have ADHD and my autistic friends are all convinced that I'm also autistic; my sibling is a fellow ADHDer and may or may not be autistic; Elders are ADHD and ??? (cluster of traits that are definitely something but remain undiagnosed) respectively.
Main thing: So, I have this communication issue with my younger sibling. (They're in their mid teens, I'm a few years older than them.) Sometimes I'll be trying to tell them something, or ask a question, and they won't respond; if I say their name a few times, they get frustrated with me (or, they make a noise that sounds frustrated, I'll admit that I don't know exactly what all their noises mean.) This isn't as much of a problem for me as it is for their parents. The elders of plumley have trouble communicating with them, and it has been known to cause arguments/distress. My sibling responds to them in ways that are harder to decipher, and they tend to make more irritated noises. (Or maybe they just get interpreted as irritation more often. I'm not sure.)
My sibling has previously described processing/registering that someone is talking to them, but not feeling the need to respond. I've asked about how we could maybe work out a means of more regularly communicating the fact that they're listening and similar, but they kinda just shrugged at me and made a confused noise. And to be honest, I feel quite similarly about the whole thing too! So, I turn to you lovely internet folks. Do you have any strategies for this kind of thing? Are there things I should be doing on my end to make communication easier? Are there alternate ways of saying "I'm listening" that aren't just saying the words?
Back when I took my Anthropology class, one of the things we covered (briefly) was different styles of communicating and how the unrecognized differences between those styles causes stress and frustration between different styles. My professor said the classic example were the stereotypical differences between men and women in American culture, as evidenced in the classic complaints "my husband never listens to me!" and "my wife is always changing her mind!"
There are people who communicate that they're listening: they nod their head, they said "uhm-hmm", make eye contact, etc. And there are people who ... don't. When a person who does this style of communication doesn't get that feedback, they feel unheard and get frustrated. And when a person who doesn't do that style of feedback receives that feedback, they think the other person is agreeing with them, so they're blindsided and frustrated when the other person 'changes their mind'.
I'd suggest explaining this communication difference style to your sibling, because while it's a frustrating thing to your family right now, I've no doubt that your sibling finds (or will find) being on the other side of the divide just as frustrating.
I'd also explain that for some people, making or maintaining eye contact can be difficult, but you can get away with looking at people's chins or ears; and if even that's difficult, that's fine, but then other means of communicating that you're listening (nodding, going "uhn-hunh" or whatever) becomes even more important.