1. When you were children, your mum dressed you in matching outfits.
2. If you went to the same school, the older sister got very protective as soon as her little sister showed up.
3. But you also went through a phase where you got very embarrassed that people knew you were related.
4. If you're the little sister, it really annoyed you when your teachers called you by your big sister's name.
5. And if you're the big sister, it was really annoying when your friends called your little sister "cute".
6. Because you're part of the same generation, you developed an identical taste in books, films, and music.
7. And films like The Parent Trap made you wish you were twins.
8. You used to fight about copying each other.
9. As soon as the older sister turned 17, she became the younger sister's taxi driver.
10. But when the older sis left home, the younger sister learnt to drive and became de facto taxi driver during family holidays.
11. It felt weird when you started dating people who are closer in age to your sister than yourself.
12. Having three years between you made the older sister prime babysitting material.
13. If you're the younger sister, you used your big sister's ID to get into nightclubs for a good couple of years.
14. But the first time you got drunk was probably when you went to visit your sister at uni.
15. It also meant you could make your sister proof-read your coursework, UCAS form, and CV.
16. But you always used to compare yourself to your big sis.
17. And if you're the older sister, you got to watch your sister go through the same milestones you did.
18. And in return, your little sister kept you updated on all the school gossip long after you'd left.
19. You swear your sister got away with more than you did at her age.
20. And nowadays you hardly even notice there's an age difference at all.
21. Because you've become best friends.
