Your phone history is ridiculous

Scrolling through your Whatsapp messages is like reading a bumper version of War & Peace, all of your outgoing calls are to her, and all of your incoming ones are FROM her (as well as, like, five missed calls from those people who want to sell you insurance).

It’s also worth pointing out that your phone calls last, on average, around an hour and a half. Minimum.

Potential partners aren’t afraid of meeting your parents – they KNOW the person they need to impress is your sis

If you ain’t got her approval, it’s over. Seriously.

She’s never afraid to give you some tough love

If you’re being a brat, she’ll tell you about it. And, likewise, if you’re being a drama queen and blowing things out of proportion, expect her to fill you in on that fact quick-sharp. It can be irksome, sure, but it helps you to be the best version of yourself that you can possibly be. And don’t worry – the arrangement works both ways…

She knows all of your deepest, darkest secrets

All the things you could never imagine telling anyone else? Yup, she knows them. And, while she won’t ever expose them to outsiders, she is pretty much guaranteed to mock you mercilessly about them when you’re alone together. That’s cool, though, because you have all the info you need to do it right back…

National Siblings Day: 20 signs that your sister is your best friend