I'm not sure if this would better belong in parenting stack I am happy to provide more information to try and help solve this. Culture context: Chinese Canadian.
Problem summary: My sibling (mid 20s) takes a shower and brushes teeth late at night (after midnight around 1 to 1:30 AM) which wakes me up as I try to sleep because we now live in a Jack and Jill setting(bathroom between 2 rooms). I would like to think the best way to approach this would be to simply explain my problem of sleep being interrupted and offer solutions, but it's ignored.
I suppose they believe I shouldn't need so much sleep (I find I need 8-10 hours), and I should live like them sleeping late.
They are plenty of "issues" with my sibling. Enough text that it could belong in another post in parenting or interpersonal stack exchange. In summary (with regards to Steven Covey's 7 Habits of Effective People) they live a very "pleasure centered" life. Otherwise they "hate waking up" which may be part of why they sleep late not wanting to go to sleep and deal with another day. They tend to wake up around past noon 2-3 PM.
I haven't dealt with their "issues" really as I'm not the parent. I have some resentment for the sibling due to the dislike of me and refusal to share in childhood, and I've been very busy with my own share of work (school and work terms). I don't find I have as much time or interest to drown in video games and shows to have easy common interests to speak of.
Sibling doesn't seem to care about anything besides enjoying their debaucherous lifestyle of doing whatever they want whenever they want. They have a part time job (I don't get an impression they don't care or seem to be trying very hard to get full time somewhere), play a lot of video games, watch movies/TV and browse the net in their room on their desktop or phone when out of room. They don't really contribute any housework either, and they don't really care about anything our parents try to get them to do or ask. My parents seem more and more resigned as time passes.
I've previously tried getting them to go to the gym with me, but they don't accept the invitation, despite they fact I believe they've had a gym membership for a very long time.
I haven't been living in this house for very long as I've been very busy doing school and work terms elsewhere.
Possible solutions/approaches and my thoughts of how they may fail. I thought it would be best to propose a few solutions to my sibling rather than nag them about the problem.
1. Ask sibling to shower and brush teeth in grandparent's downstairs bathroom where it won't wake me up?
Caveats: They probably don't even want to the walk down there despite the short distance, see/hear/smell grandparent, plus it smells like old person. They'll also probably ask why can't I sleep in grandparents room instead if I suggest this. Also maybe this isn't really fair to grandparent to possibly be woken up? However grandparent is quite old (high 90s in age, dementia, etc) and hard of hearing though, they spend plenty of time sleeping. Nowadays since grandparent can't do stairs sibling can conveniently spend most of their time upstairs and never have to deal with them.
2. Ask sibling to shower and brush teeth earlier, even going as far as to ask them to do it everyday ~10PM, again.
Caveats: Done this before they don't really care, and even when I nag them to do it earlier they necessarily won't. Plus they might be "too busy" in the middle of a online game they can't pause, or want to finish an entire movie or TV episode. Like many humans they don't like being told what to do, or asked to do something.
Edit: Months ago I said something the lines of "hey can you shower earlier so it happens before I try to sleep?"
The reactions I get is annoyance and disbelief, and essentially lip service to that it'll be done which it doesn't.
3. Get parents to ask sibling to shower and brush teeth earlier.
Caveats: They'll just ignore it as usual, or pay lip service temporarily. My interpretation is their habit and endless debauchery is more important than my sleep. How to make this a habit to stick and make sibling want to do this is what this solution lacks.
4. I go sleep in the basement where I'll be stuck dealing with the noise of the water tank and heater instead.
This could attempt to avoid the problem but it doesn't really solve the problem of a lack of respect, and I don't like the idea of letting sibling just walk over everyone else in the house and setting another precedent of they can do whatever they want and everyone else has to work around them. Also problem doesn't necessarily get solved as now I have the water tank and heater instead.
I suppose I can try them all. I have previously slept with ear plugs however I don't enjoy it and don't want to be wasting money on ear plugs for every single night. Ultimately I feel rather pessimistic as I don't understand how you can really negotiate with a party that doesn't really care or consider your needs reasonable.
Later I hope to move out once I get full time work elsewhere, but that'll be in the future. I would appreciate any advice I can get, perhaps I am approaching the problem wrong and I must solve other related problems.
I previously read Crucial Conversations a long time ago but still feel like I'm at a loss of how to approach this.
Edit: Upon proposing solution 1 and 2 to my sibling I was brushed off with as many "yep" and "yeahs" quickly to get rid of my, as I was interrupting them in a turn based card game, which doesn't demand immediate undying attention in my opinion.