Families are like a complex machine, and older siblings are the oil that help it move more smoothly. Therefore, you deal with a lot just because you were born first.
You're a freelance babysitter.
Oh, you have plans? Sorry, you have to watch your sister tonight. As soon as you become old enough, you are the one your parents come to when they have to work late or have plans that always seem to inexplicably clash with your own. And, of course, the frozen pizza in the freezer and the soda in the fridge doesn’t really make up for the lack of payment. Even after your younger sibling grows out of the babysitting age, you’re still in charge of her, always the responsible one. Forever the older sister, forever the babysitter.
You have a mini-me.
After spending 24/7 together, you begin to realize that you may have a younger clone. It may be all of a sudden, or something subtler over time, but you’ll soon notice how similar your younger sibling is to you. You begin wearing the same clothes, and most of the time it is due to some involuntary sharing on your part. At first it’s annoying, but eventually you become accustomed to her hanging around you and rummaging through your stuff. People do say that mimicry is the highest form of flattery.
Your sibling will bug you to no end.
You two are closer than anyone else, but that means you fight and argue more than anyone else. You will never disagree with anyone like you do with your younger sibling because no one else’s opinion matters more to you. Even the days when you want to be as far away from her as possible, you eventually plop down on the couch with one of you apologizing, both verbally and nonverbally.
But you won't let anyone mess with her.
Unfortunately, “siblingship” also comes with a protective nature. She’s your kid sister, so you definitely won’t allow anyone (other than you) to mess with her. You’ve pulled her out of the way when the neighbor boy lost control of his bike and listened to her when she told you she was being teased by a few girls at school. Because as much as she pushes your buttons, you don’t want people pushing hers.
And sometimes you have to whop your younger sibling into shape.
When she acts ridiculous and needs someone to tell her to shape up, sometimes you’re the only one able to do it. As the older sibling, it’s your job to tell your sister when she messes up. You want her to be able to learn from your mistakes, but be able to make her own as well.
Sometimes your younger sibling has to whop you into shape, too.
Even if you don’t want to admit it, you’re occasionally in the wrong as well, and you need someone to show you you’re wrong. And sometimes, she’s the only one you’ll listen to as well. You’re the older sibling, but you also need help from making mistakes.
But you'll always have someone there for you.
Any time you need to talk or rant or just sit and relax, you will always have your younger sibling there to fill the spot next to you.