I don't give advise so I will just write about what happened in my family.
OUR PARENTS WERE THE PROBLEM!
As a little kid, in awe of our parents, I would never have seen this nor figured it out. My relationship with my older brother was doomed from the beginning because our very ignorant parents FAILED to mentally prepare him to lovingly accept me from day one of my life and then, after I arrived, they further FAILED to train him to happily accept me as his beloved brother and friend instead of an unwelcome, unwanted and much HATED INVADER & threatening enemy of his. As soon as he decided that I was his enemy, he savagely punished me from then on while I innocently loved and respected him since I had no reason to resent him like he did me.
OUR PARENTS further made things worse by allowing him to brutally punish and abuse me for many years WITHOUT either protecting me or encouraging him to treat me better. I now believe that they thought we were real FUNNY in our innocent and non-damaging toddler skirmishes over toys and attention.
So the unhappy and unhealthy relationship between my brother and I was all a sad and direct consequence of VERY BAD PARENTING.
Then, when our little sister was born about 4 years after me, all the resentment, hate, jealousy and bitterness started up again but in our sister's case, we did not DARE abuse her or dad would have MURDERED us since she was his precious favorite.
OUR PARENTS WERE THE PROBLEM from day one and it stayed like that until we were in our mid-teens. Fortunately for us kids, we did finally develop some respect for each other but we never did become good friends to this day all because our rotten parents would not allow it and none of us, except me, has done any family or emotional work to undo the damages our stupid parents did to us back then and replace it with normal sibling love and respect. I don't expect my siblings will ever see what our parents did to us so I guess we will just be polite, distant and cool siblings from now on! It sucks!
good luck,
jim