Apologies as I don’t have the source for this! I am not 100% sure this is an exact match, but considering it was the first that popped up for me and is a brand that Margot very commonly wear, we’ll go with it now! A fan was very lucky to catch a picture with Margot, who was wearing Faithfull the Brand Phoebe Dress. It can be found on Shopbop for £113!