Should I hit my brother?

Important question: My brother is 19 months old and I and I sometimes fight because my brother has no boundaries! And in the end my parents always blame me. Today he came into my room at 6 a.m. without knocking and then claimed that I had jerked off (which isn't true). He went so far as to tell my parents and make fun of it, even though I told him it wasn't funny and then he laughed. I don't know what to do. If I hit him it's my fault again and when I talk to my parents about it they ignore me. What should I do?