You were Itachi and Sasuke's little sis/bro. Itachi's caring and kind against to you. However Sasuke's opposite of hım. Is he…jealousing you? Definetly, he doesnt like the attention Itachi gives to you. For Sasuke, Itachi must only care about hım. So mostly he ignores you.

Your parents are outside of the Konoha for a meeting so you're staying with your brothers

Sasuke: Oi, brat. The supper's ready. Why are you keep waiting us!?

Itachi: Stop Sasuke…Lets just go. I cooked your favorites.