Saying it on a T-shirt is nothing new - but just lately, we've noticed a pointed new trend creeping in.

Political messages are passé. These days, it's all about bigging up your famous friends.

It's all Rita Ora's fault. This week, she tipped us into three's-a-trend territory by stepping out in this homage to Kate Moss, with whom she's regularly spotted on the London party circuit.

Plus, who could forget Jourdan Dunn listing off some famous model buddies - and adding herself to the cannon - in this cool T during the s/s 2015 shows?

But our favourite moment of mutual-celebrity-appreciation-via-T-shirt this year remains with with Ryan Gosling and Macauley Culkin.

Don't understand why? Read this immediately.