Potterlock - Sherlock and John meet waiting to find wands at Olivander's. They try out a few wands and none of them are working for them so Mr. Olivander hunts around for a very specific box. "These two wands refuse to be separated," he tells them, "I've had to store them together ever since they were made." When Sherlock and John waive the wands they're a perfect fit. When they get sorted at Hogwarts, John goes to Gryffindor and Sherlock asks The Sorting Hat to keep them together.