I have an older siblings that hates me for some reason
Do u know any of the consequences or if something happened in between you two?
Did your other sibling hate you from when you were born or did she or he hate you from a moment very precise?
Since I was born
And you two are the only children? Or do you have another sibling?
They might have secret animosity towards you in some way. Maybe towards you and your parents relationship… you have to do the work and figure out what that animosity is