why do people hate their brothers or sisters

i don't think brother can hate his sister or sister can hate his brother. It is love in the form of anger it's appear for a seconds. Hate in the sense of true and deep love. There is not word called hate in this relationship.

For me maybe because sometimes in the family, there is what they called revalry. Most of the time when there is a closed-age gap between sisters. Thats why parents should see it that in a situation wherein they only have 2 daughters, once they give things, favors, with these children, fairness should be exercised. Because once one of the kid felt of unfairness, well, the feeling of hatred would rise. So as long as they are still in early age, proper treatment should be exercised so as to avoid this kind of feeling. If parent cannot afford to provide both kids at the same time, well just a matter of explanation between the two of them.

Do brothers and sisters really hate eachother, i love my sister to bits we get on great i could never imajine hating her.

I don't think that brothers/*sisters hate their brothers or sisters.I love my sister very much like I love my daughter.She is a part of our family so how I can hate my own sister.:)

The love hate relationship between siblings are really natural. You hate your brother for doing such a stupid thing because deep inside you care for him.