You were inseparable as kids and nothing's changed, even if you now live miles apart. The bond you created means that there are no secrets between you and your shared life experiences mean you know each other inside out! Here's a list of life experiences that we all share with our childhood friends...
1. Those embarrassing childhood snaps!
Silly poses, bad haircuts, embarrassing clothes... All stored away in family albums ready for your parents to take out and show your new boy/girlfriend! You as goths, you with mullets, posing in your favorite Christmas sweaters, a video of you both practicing your latest ballet moves - trust us, we've all been there!
2. Reminiscing about your childhood
© Paramount Pictures
Who doesn't feel reassured when reminiscing? The ups and downs that we shared with our special childhood friends are subjects we discuss when we're older and wiser! Whether it's happy experiences or life's tragedies, our shared past forms part of who we've become.
3. You've seen it all
© Camilotorres / Getty Images
Nothing surprises old friends - you've seen it all! Barfing at a party, farting in class, falling out of a nightclub together, sobbing your heart out when you've been dumped... You're so comfortable with each other that anything goes!
4. You always ask their advice
Everything gets passed by our best friend: from what clothes to wear to which guy or girl to date or even taking major life decisions... And it works both ways!
5. You're part of each other's family
You've spent so much of your life together that you've become as close as siblings and over the years your families have merged into one big, happy clan!
6. You spent half your childhood at their house
© Columbia Pictures
You're in their family photos, you've got your own room and have even left your toothbrush in their bathroom!
7. There's no point in lying
You know them so well that you can immediately tell if they're lying. Plus you instinctively know what they're thinking, so telling fibs is a no-no!
8. You can get jealous when they make new friends
Of course you'll cover it up - we all make new friends throughout our lives, but it still hurts a bit when our best friend hangs out with someone else. That said, you're so close that you know you've got nothing to worry about and when push comes to shove, your BFF will always be there for you!
9. You know all about their private life
© Big Machine Records
You've met them all and have got all the dirty details on any passing encounter they may have had! Just remember to keep it quiet - they have just as much dirt on you!
10. You really miss them
Moving away or settling down to start a family can mean we lose touch with our old friends. Even so, you've found them on Facebook and you make sure you have Skype or Face Time sessions - the great thing about technology is that no matter how far away we are, there's always a virtual way to keep up with each other!
11. Insider jokes
No one has a clue why you're both in stitches, but that doesn't stop you from cracking up when an insider joke raises its head!
12. All those 'first times'
© Columbia Pictures
You've had more 'first times' together than with anyone else: learning to ride a bike, playing with make-up, first day at school...
13. You don't mind making a fool of yourself in front of them
You can let it all hang out when you're with your best friend. You can be your true self and leave your office persona behind!
14. It feels as if you've never been apart
Time doesn't change anything - you can spend years not seeing your best friend, but when you do hook up it feels like you've never been apart!
15. They know all your secrets
They know EVERYTHING and won't tell a soul. They may even know you better than you know yourself!
16. You'll be together forever
You'll grow old together and can't imagine a future without your BFF. You may even decide to book into the same retirement home and pick up where you left off!
17. Nothing will tear you apart
© United Artists
Whatever happens, there will always be an unspoken 'until death do you part' friendship clause!