Dudley's tail
Guys it just dawned on me, when the Dursleys take Harry to Kings Cross the first time, they say he's lucky cause they were going to London anyway to see a doctor about Dudley's tail. They went to St. Mongos!!!! Think about it, they must have already taken him to a doctor by where they live, but couldn't have it removed! They needed to take him to the Healers and of curse Petunia would have known about St. Mongos if she knew about the demontors!!!!











