Campbell created a collage of her favourite photos of her friend, which she shared on Instagram with a caption addressed to “Little Wagon” her nickname for Moss - who turned 43 on Monday 16 January.
“#LittleWagon here comes that special day,” wrote Campbell.
“Happybirthday @katemossagency #katemoss sending you all best vibes and wishes wagon.”
”We have a come a long way together and I cherish our bond, our honesty has kept us always there for each other #truth #southlondongirls we will always be,” the Streatham-born model continued.
“Have a great one, I love you wagon.”
We’re dying to know what the pair were discussing in the photo of Moss in a pink slip-dress in the bottom right hand corner.