"Aren't they," Sherlock grinned as he took another jelly slug. Happened to be among his favourites. Even if disliked slugs. A lot. He couldn't wait until they were old enough to go to Hogsmeade. Then he would get to visit honeydukes... The sweets in there sounded amazing. "She is one of the four founders of Hogwarts and was in charge of Ravenclaw house." He smiled. "I should probably explain more. Basically there were four founders of Hogwarts - Godric Gryffindor, Salazar Slytherin, Rowena Ravenclaw and Helga Hufflepuff. They each selected students to be in their houses for school and that's how it all started. Basically everything is done in houses. You're always in class with your house and usually one more, you share a dorm with the other members of your house in the same year and of the same gender, there are specific dining tables for the houses but I think it is possible to sit with friends at other houses after the first night... It's pretty big. There's also the house tournament, where the house with the most points wins, and the quidditch tournament. I don't know anything about quidditch and I don't care. If you wan to know about that ask Lestrade, he's on the team. He'll be captain next year when the current one leaves undoubtedly. I can explain about each of the houses if you really want though." He tried not to laugh as John asked about the picture leaving. "Well you wouldn't expect her to stay in your card the whole time? She does have other things to do... She's undoubtedly gone on a trip to join someone else in a picture. Probably another card. They quite like to visit their fellow paintings and pictures."