To think this is asking a lot?!

Sounds like Person B has a lot of free time, perhaps they can walk

Person A is unreasonable for writing all this A & B nonsense instead of just saying ‘my brother’ and ‘my parents’

AcrossThePond has nailed it really. There is no reasoning with unreasonable people. They cannot conceive of a situation in which they are not the most important factor.
why does Person B think their mental health is more important than Person A’s health? Becoming chronically overtired and resentful is not a recipe for good mental health. Person B is asking far too much. They don’t understand this because they take steps to ensure they don’t do more than they can manage. It is completely reasonable for Person A to protect themselves in the same way. Just because you can manage more, doesn’t mean you can manage everything. You are aallowed a threshold for what you can do.

Obviously it is asking too much. But if person A agrees to do it, that's their own fault. Say no!

Cheeky fuckers will remain cheeky fuckers as long as there are dumbass people out there allowing them to be cheeky fuckers.

Say no.

B is extremely cheeky and needs to sort their act out.

i have mh issues i still learnt to drive beause i didnt want to beome a burden

tell them to jog on

OP, are you reading and taking in this?

No is a complete sentence. You don’t have to justify your reasons.
Look I’ve had a variety of mental health problems and I’ve had to continue to work, drive, look after my kids and get help. I didn’t have a choice.
You need to establish some boundaries and say no, it doesn’t work for me.

A few reasons I can think of that might obligate A, at least in part, to help with a solution:

• If B’s living situation (i.e. in a rural location that makes transport difficult) is down to B to any extent.
• If A is getting accommodation from their parents and their parents request it as part of reciprocation.
• If A is responsible to any extent for B’s inability to function to a normal extent
• If A is responsible to any extent for B’s lack of resources

Even if any of those (or similar) held true, that wouldn’t necessarily make the request as it stands reasonable.

Absent some sort of reason that indebts A, it seems like a totally unreasonable request that treats A as a tool to fulfill B’s desires without any reciprocation or consideration of A’s needs or desires.

So the question is - Is this post just a vent at B’s audacity, or is A actually entertaining the request? And if they are considering t - why? What pressure is being applied?
(And if you are A, OP, could you just say so? It’s awkward as fuck to talk about a situation like this).

A clearly lacks boundaries and needs to learn to stand up for herself and cut loose from
person B a bit more

I would be interested to know what mental health condition limits you (one) to working 2h a day. In my experience either people are too unwell to work at all, or well enough to work full time but potentially needing chunks of time off intermittently due to poor health.

I agree with a PP there's no point giving reasons why not. Just say sorry you can't. Then suggest other options for them. Cycle to family member, move closer, get a loan from family gor driving lessons etc.

@Foodfrezy

I would start again, sack this thread off.

Wording I would suggest is

My brother is a lazy workshy git who cant drive because he cant afford it as he only works 2 hours a day. Could work more but wont. He expects me to pick him up after I finish my FT job (10 hour days) and drive him a 40 mile journey to see family members, several times a week. He is certain he is being totally reasonable in asking this.

AIBU to tell him NO?

B needs to take responsibility for themselves. Up their hours, earn more and learn to drive.

Gosh I bet you can almost see entitlement oozing out of person B.

On top of asking to much
they're taking the piss.

If you are siblings why does B need to visit this "family member" several times a week when you - presumably - don't need to?

What is this special relationship between B and the "family member" that you aren't a part of?

Not that it matters, but how far out of your way do you have to go to pick B up and then drop them back at their home?

What B expects is obviously unreasonable. It's up to you what sort of resolution you propose. You could stop it altogether or say you are willing to do it once or twice a month, but no more. And you decide what days those will be.

Completely unreasonable request

B can totally fuck off.

A needs to say "sod off, B" and refuse to engage further. 40 mile drive after a 10 hour shift, regularly as a favour? Blow that for a game of soldiers.
No. Absolutely non.

@Foodfrezy

Posters have given a plethora of reasons to give B as to why you can't do what they want. But the problem with entitled people/golden child is that a reason that does not affect them directly simply does not compute. Costs you too much in petrol does not compute because it doesn't cost B anything. You are too tired after a long hard day + commute doesn't compute because B isn't tired after working just 2 hours. Any reason/excuse you give simply will not compute, so don't bother offering any. This is the exact situation in which the MN chestnut of "No is a complete answer" 100% applies.

You say no, they say why, you say because. No Why Because, No Why Because & repeat ad infinitum. I guarantee they'll get tired of it before you do.

YABU for all this A/B nonsense when it’s clear who’s who and doesn’t matter

I bet the sibling would just say how much worse theirs are.

What exactly are B's mental health issues?

How can they live on 2 hours work?

Why did they choose to live rurally?

What age are they?

The passenger does not get to dictate when the driver is available.