I've just got a feeling that there is, might be completely unfounded, but she is very very antisocial in the mornings, doesn't say a word to anyone. In the afternoons the coke appears and she is suddenly the life and soul, with an occasional vagueness and wobbliness about her.
I'm just tempted to have a sip whilst she is in the ladies. Not sure what I would say to her if she caught me out though .