I was in a gift shop in Windsor when a little Old Lady was purchasing a cap. It was hot and sunny and she told her friend she just wanted something to keep the sun off. She picked out a cap with an enormous great ganja leaf on the front which she thought might be a tree.
Do you tell her? It might save her some embarrassment, but it would be rather funny to have a respectable looking little old lady pottering round the home of the Queen with a cannabis cap on.