My daughter is six and a half and she started asking about her brother I think at 4. He is two years younger and when the therapists would come to our house she would get jealous. I know it might be too simplistic but I told her that Emerson had learning problems. It was harder for him to learn then her and he needed some help from his "teachers" His teachers also needed to teach him how to play and we needed her help. We also said that his 'brain gets fuzzy' sometimes and he feels like 'the volume is turned all the way up" (We actually turned the radio up full blast for her so she would know what we meant)
Now she is dealing with some jealousy that he is reading better than her. I tried to tell her it is just his super skill and pointed out all of the things she doesn't have problems with (like going to the bathroom) Having a sibling on the spectrum is a hard thing for a child to deal with. We ask alot of her and she always amazes me with how she handles it! I try to make it as fair as possible but it doesn't always work out that way :(
We have also been having to work on apologizing. He will hit her or mess up her things and he is doing REALLY well at apologizing after. She doesn't want to accept it though. After we had a talk about it and I told her that it is hard for him to understand how she feels when she is upset, and we have to help him even if we are mad at him, she has been doing a better job "helping" him apologize. Yesterday they were fighting and she was crying and all I said to him was "Meadow is mad at you." He started crying and "went to bed" I was SO surprised that he was upset because I told him she was upset. After that they looked at each other and started laughing. I live for the moments that seem typical! <3