How old are you? No, really! How old ARE you?
Do you ever wait for a certain age, and when you get to it you start feeling everything changing slowly?
Being a grown up is not about the age, that's just a number, could be a number of years that it took to make you who you are, or it could be the number of years that you've spent being that same 12 year old trapped in an older person's body.
When people do or say things in front of you, you know when to talk and when to shut it. You have to know when to talk back and when to spare yourself the waste of time you spend at leveling down to some people's minds. You should know what to ignore and what to take in, you should know how to criticize without hurting anyone, it never hurts to talk in a nice way. I'm known for my honesty, but I've never said anything that hurt anyone at all, there's a time and a place for that.
Most people when they first meet me I'm mostly awkwardly quiet. They'd think that I know nothing, but after a while they notice how I only talk about what I know, and that I never judge or make fun of anything unless it's out of respect or it's followed by "no offense!" or has good timing. So when I meet people that don't know my age they think I'm at least 23 years old, but my family think I'm still 18 or less, which is fine because I know that I've stopped growing up at 18, but I know I've been through enough to make me understand, react to things, say stuff better than people double my age.
People don't always have to comment on everything, they don't always have to argue with something they don't like unless they'd know the person they're arguing with is understanding or have an open mind. And please, for the love of god, don't ever call yourself open-minded if you can't stand being in a room and not judge people around you. Or at least learn how to react.
One of the things I really hate about people when they go like "I say the first thing that comes to mind" or "what's in my heart is within my tongue" and they think it's always a good thing, and they're just proud of it. You get what I mean...
The less you talk, the more you listen, the more you listen, the less you sound stupid when you talk.
So let me ask you again, how old are you?