I've been a twin for nineteen years, and I would like to clarify that I'm a fraternal twin. Usually, by this point I would get a somewhat less excited audience, but it's still AWESOME to live a life with a second, slightly taller half.
Below are things you experience if you're a fraternal twin.
1. "You guys are twins? You're messing with me." OR " You guys are twins?....I can totally see it"
I'm surprised by the range. I think my sister and I look completely different, but there are people who can't tell us apart.
2. The younger twin can look older than the elder twin.
This is not true in my case, but I know other sets of twins who are like this.
3. Whenever your twin messes up, you get dragged into being punished with her/him.
My parents always assumed that we help each other plot our misbehavior.
4. They probably make that assumption because we have our own "family within our family."
What I mean by that is we have a whole relationship separate from our family. We used to have a made-up language, and I trust only my sister with my deepest and darkest secrets. I don't have ANY filter around her AT ALL.
5. You're compared to each other.
I thought this wouldn't be the case because we're fraternal, but it still happens. Friends of the family would comment on our different appearances and personalities; God forbid I don't look our age and my sister does.
6. You're forever merged into one entity in people's minds.
Again, this is a thing even if you're not identical, and it's probably the most frustrating part of being a twin. Wherever I am, our mutual friends always ask me where my sister is or why she isn't with me. If she does well in school, I must be doing well too.
7. I complain about #6, but we probably enforce that thinking by being together all the time.
It's so easy to go places together because you get a person to talk to in a new place rather than awkwardly standing around.
8. We could never relate to twins in movies.
But I'm Annie and my twin is Hallie.
9. You often know exactly what your twin is thinking/ will say next.
Twin telepathy is a cool thing to say you have, but I'm here to say that it's not a thing. Once you experience nearly every day with someone and observe each other's reactions to certain events, you naturally develop a sense of what the person would think/say next. This way, no context is needed for most of our conversations.
10. Because of #9, you become each other's therapists.
I'm probably not insane right now because of my sister. We know each other so well that she knows exactly what to say to make me feel better and what to do to solve a personal problem. It also helps that she knows all my personal demons so she can address my problems based off of them.
11. "What's it like being a twin?"
I still cannot fully answer that...but I guess that's just a twin thing. =D