We do love keeping up with the Kardashians, but we'd totally forgotten that these two were childhood pals! Yes, Kim Kardashian has treated her Instagram followers to a blast from the past with this snap of her and Nicole Richie at the tender age of thirteen. Aww! With bushy eyebrows for Kim, braces for Nicole and matching white T-shirts for both, it's a wonder they've become two of the world's biggest style icons.

The Kardshians have been elsewhere on Instagram too (quelle surprise) with Kendall posting a snap of her with sister Kylie behind the scenes on Fashion Police co-hosted by Kelly Osbourne while Kelly herself shared a photo of her with her bodyguards. Rita Ora also takes a trip down memory lane and shares snaps of her with Queen Bey and hubby Jay-Z at last summer's Wireless festival.

Cara Delevingne shows us a video preview of the new YSL beauty campaign. Cara has been the face of YSL for a while now but now she is accompanied by her British bestie, Jourdan Dunn. It looks like they had a right laugh.  

In other instagram news, it's back to reality for Cheryl Cole as she waves goodbye to her best holiday ever! Ellie Goulding finds a Jessie J at the Brit Awards and Heidi finds an LL Cool J. Alexa Chung is updating us on her trip to LA with Pixie Geldof...road trip!

Take a look through the gallery above to see the best pictures on Instagram today...