Alongside Millie Bobby Brown‘s Enola and Henry Cavill’s Sherlock, the role of the third Holmes sibling, Mycroft, will be played by Sam Claflin. While Mycroft is traditionally portrayed as the most serious –and occasionally dull — Holmes brother, Brown recently told GMA that he was actually quite funny on set, which led to a lot of laughter. Brown was apparently impressed by Henry Cavill’s ability to transform from his laughing self to his serious character in an instant, while she sometimes needed to remove herself from the set to get ready for the next scene. Brown explains…