We have been friends since we were 3

You are 12? Don't take this the wrong way, but don't tell her yet. You are both young, feelings are sure to change every day- for both of you. Just enjoy the friendship & see what comes of that in time. :) Patience never hurts when it comes to love. As a matter of fact, it is key. ;)

Haha I can promise you that you won't feel the same in general in a year. Im 18 and I grew a lot.. you have a crush on her and its fine I remember when crushes were all sappy and innocent.. anyway just hang on to her as a friend don't push her or anything. Your all still very immature so just continue to be her friend and focus on yourself and school.. your barley in middle school right? Just have fun and don't take it too serious

Hi

I'm not going to say nothing about your age, the point of the matter is, she has someone respect that. And respect yourself and leave her alone.
Its hard I know. But you can. And will be able to do it :)

All the best