I would just tell her, I mean it's not like you're telling her that you're in love with her. Just tell her and she'll probably just say thanks I feel that you're like a little brother to me.
You don't have to tell your cousin such things. If you don't know how to do it, don't do it.
Tell her to slap dat pig.
So that your mother or your older sister will tell you what not to do and what to do , so they will guide you and tell not to worry
this not important to tell my mother or sister about this my thinking that first i tell my best friend about
tell her your annoying trust me
Tell your parents.
be honest and tell her what good you see in her
It will be hormones (I know everyone says that, but its true). It's good to be a protective older brother but doing anything inappropriate is not right. Think about what is right for the little sister and her life.
YES, the older brother/sister gets to be the boss no matter the circumstances. The younger brother/sister always have to listen to the older one. If they tell you to get of the sofa, the younger has to leave no matter what.
Think of something personal and tell them.
tell a adult
Tell your guardian.