My sister was born in July of 2006 and I turned 12 that August – and for most families that's a huge gap.
But in this day and age, families come in all shapes, sizes and ages.
So, if your brother or sister was born years after you first emerged on the planet, here are 8 truths you'll know to be true:
1. People will think you're the mother
And considering I still look about 12 and she's now 10-years-old, people get seriously confused.
You will mostly play along when people call you 'mam', but still get a little freaked out.
2. Even nurses are mistaken
The first day I went to visit my sister in hospital, my mam popped out to the loo and I was holding Áine in my arms. The nurse then came by and STARED at me and said, "I've seen mothers young, but not that young."
Erm… OK? Check yo' facts, woman…
3. You hear about your friends fighting with their siblings and wonder what the fuss is about
Because there's such a big gap, you probably moved out of home a few years after they were born, so you never clashed while growing up.
Don't get me wrong, I still argue with my sister, but stories of sibling rivalry really amuse me.
4. They have it SO lucky
Your parents basically tested everything out on you and if they thought some activity was too dangerous to do, you weren't allowed do it.
But, at this stage everything has been tried and tested, and your parents realise that no, she won't die if she gets a pair of rollerskates.
(Yep, rollerskates were too dangerous for me so I had to RUN beside all the other kids skating down to school… thanks, mam.)
5. If you were an only child beforehand, having a sibling (at first) was seriously weird
Who is this person who just came screaming into the family? How do I hol… oh crap, I just bashed her head against the wall.
You just weren't used to looking after another person…
6. You're basically their cooler, younger parent
You worry about them non-stop, but are way more understanding (and chill) than your parents.
And if your sibling can't get around your mam or dad, you can bet they'll come to you next. And you, of course, will give in.
7. You still hold their hand
Since you were old enough to remember them being born and you saw them growing up, you're fiercely protective.
And if you drop them off at school, you still give them a kiss goodbye even though it's SO not cool *death stares being sent your way from the school gates*
8. But honestly, they'll always be your baby
You have a special bond with them that absolutely nobody else has.
And even though there's years between you, you just get each other and will always be there for each other.
Oh, and while we have you; don't forget to have your say in the inaugural SHEmazing Awards this May! It's time to vote, and you can do it right here!