Lady Mary Charteris reveals she is '6 years, 5 months and 22 days' sober as she DJs at the launch of Delevingne sisters' alcohol-free prosecco

The London-based socialite, 37, took to Instagram to share a snap at the launch party of a non-alcoholic rose by Della Vita - the brand created by Chloe, Poppy, and Cara Delevigne.