Ariadne was puzzled already, and the class had just started. She tried to find an answer for the question Professor Hadley had just asked.

'A mere coincidence could be...meeting a childhood friend on the street after many years in which you hadn't seen each other?' she replied, after having raised her hand. That's what happened to her mum on Diagon Alley, she had bumped into a friend she hadn't seen in 10 years or more.