Every day he is becoming more like her.

[AppealToReason]

EVERY day I can see my younger brother becoming more like my sister. The subtle attitude, staying out longer, no longer listening to anyone. I.can't.fucking.stand.it. He is in the 6th grade, with a phone due to shit parenting, and his attitude is fucking annoying, especially around friends.
He called today while we were driving home from school demanding my grandmother pick him up where he wants to be picked up at, not where she told him to be. Mistake one, giving me a fucking attitude.
Of course, she gives in. She never fights back and it's irritating.
Anyways, I told him that he either goes where she tells him to, or he can walk, and not to give me his little fucking attitude. Hour goes by, he comes home with a friend, claiming he waited in the spot the whole time. Mistake two, lying to me.
I asked him why he's being so nasty, no reply. I ask him to apologize, gives me attitude. So I flipped out. He cussed in front of me, mistake three.
God, I haven't cried in front of anyone since I was in the third grade. Not when family died, not when friends died, not when I had the shittiest days and felt like dying, but I couldn't control it today. I couldn't stop shaking and crying in front of my grandmother.
I'm so tired of this shit. I can't stand my family any longer. My second sister is the only sibling I can stand as she never disrespects us. My other sister and brother are such spoiled, conceited, fucktards with no respect. I love them on their nice days, but I'm tired of this bullshit. My sister put this family through hell, with her multiple arrests for drugs, fighting, blah blah blah. I can see him becoming her. I can't let it happen. I can't fucking deal with it again. My mother doesn't give a shit, so I have to prevent what I couldn't the first time.
So, what the fuck does one do to prevent him from becoming like my sister?
/rant

[TeddyBearRock]

The same thing with my brother (but he's 4, doesn't have a phone and what not) anyway. Just tell your mum you won't look after him any more, that what I did, and it worked

[AppealToReason]

There is absolutely no way to get through to my mom. She's a shithead who won't admit she has a drinking problem, spends money on her friends, doesn't buy her kids food, borrows hundreds of dollars from family without ever paying back, and is just a leech. She fails at parenting, being a mother, and a good human being. She may somewhat care about us, but she sure as fuck won't show it.
Thankfully, aside from when I was younger, I don't live with her. My brother should, but he stays here with myself and my grandparents, which I can't stand. We don't owe him anything, he stays here because my grandparents love him, but he's too fucking stupid to see it. I ask him to take out the trash, he'll tell me okay. I came back an hour later and it's still there, he'll tell me "I'll do it when I want to".
God.God.GOD. I'm still shaking. I can't handle this fucking selfish behavior from any of them any fucking more.

[Desuetude]

Have you talked to him about it, asked him why he is being so belligerent.
Maybe your grandparents can put down some ground rules and punishments if they're not kept to. If he has boundries put in place then he's likely going to listen to you as well. You just need to establish to him somehow tat you are head of the house and he needs to respect you.
Getting angry about it any the way to go but saying that is ironic because I act exactly the same way. Just try and calm yourself down take a moment and just deep breaths in and out if you need to. He is going to be looking for things that will make you snap so try nit to give him any.
However you are his brother and should not take sole responsibility for bringing him up. You don't need to do all of this for him but you do and I don't know if that's because deep down you care or because you feel it's your job but it isn't.
It's ok to cry, better to let everything out like that than holding it in or finding a more harmful way of going about it. Don't feel you have to be macho and show no fear, everyone needs someone there for them in the end.