Hmmm, without knowing the situation this sounds to me like it might be jealousy. This makes the idea of forgivenes that much harder I believe.

I agree with the above that it sounds like your parent's hands are very full. I choose to think it is not a matter of opting to give one child more attention and ignorring the other. It seems your brother needs more attention he receives it accordingly. Is your own relationship with your brother unfixable. Would helping him out yourself provide to you any sort of satisfaction?

And the relationship you do have with your parents. Do you feel comfortable enough to sit them down and let them know your concerns of being lost in the frenzy to help your brother?

For me the turning stone wasn't me talking to my parents but instead talking to my brother about my feelings. He actually admitted to his playing a part in getting more attention. He stopped 'demanding' their attention and things really improved - including what was a horrible relationship I had with him.