How do I help him stand up for himself?

A little bit of background for those of you who aren't intimately familiar with my childrens' personalities (whatever): Child 1 is 9 and has autism. He is sweet and smart and mellow and kind and a little shy, even around us. Child 2 is 6 and does NOT. He is crazy smart, funny, feisty, adorable and very outgoing.

Child 2 is an excellent person to be helping Child 1 learn to socialize, because he's pushy and demanding (but in an awesome way, of course) and you have no choice but to be aware he is in the room; just in the past 6 months I've noticed a change in the way they interact and play together. It. Is. Awesome.  They have back and forth conversations,  one asks, the other answers, I don't have to do any prompting or even be in the room. LOVE. IT.

Whenever there's a turf or possession war, my first response is to say "don't talk to me, talk to him about it," for a number of reasons, but mainly because I want Child 1 to learn how to do these things without my help and there's no safer place for that than with his brother, in his own house.

HOWEVER! Now that they're interacting so much more (yay) I find myself constantly walking this line between trying to help Child 1 stand up for himself, and not showing any favoritism. For example, the other night C1 asked me to find him a flashlight so he could play with it. About 10 minutes later I see that C2 is playing with the flashlight. I asked him why he had it and he said "C1 said he was done with it." So I ask C1 if he was done with it and he said he was, but I know that wasn't true because I had hunted around the house for the damn thing at least as long as he had been playing with it. I sat down next to him and told him that he doesn't have to hand all his toys over whenever his brother asks for him, if he's not done he should say he's not done. He nodded; he understands this concept, but it's not what actually happens.

It felt weird telling one child, and the older one at that, that he needed to stand up to the other child. I can't make him be more assertive, but I know he still wanted the flashlight, even if he said he was done with it. And if Child 2 had heard that? Man he would have been pissed. He's already complaining about how C1 gets to do more stuff than he does (not really true; he's also very dramatic).

I hope I'm explaining this properly, I feel like it's just a crazy jumble of words, but how do I help Child 1 learn to stand up for himself, in this safe environment, without making Child 2 feel bad? Any suggestions are appreciated.....

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