My sister is bi-poler, and my advice is it depends on how severe it is for her (or him?) and how calm and level-headed you are

I've always had a good relationshop with my sister, but I am a very calm person (maybe because of this?). It can be hard sometimes, like when they do something ridiculous, can you blame them? Is it their fault, or is it out of their control and therefor not their fault? I dunno.

For example, suppose they request something ridiculous. You can either:

1) comply, but risk giving him/her the impression that they 'deserve' to get what they want whenever they ask for it.

2) not comply, but risk infuriating them. Is it worth it?

I've been faced with this choice many times. Obviously each situation is a little different, like if she says "pass me that fork" you probably should, but if she says "cook all my meals and clean my house every day" you should probably not.

But yeah, if during one of their bad moods you can keep calm, talk in a normal voice, and think logically (not forgetting their condition) then you got a chance I reckon