So that explains it!

"The trouble is," says Star, "that I think of something to do and then I do it. Then I think about whether or not I should have done it. Then I realise I shouldn't have done it ... but I have."

That would explain why in the course of one day trip to the zoo she:
- threw a (mercifully small) pinecone she was holding at an ostrich.
- pressed a button on a drinks machine that told it she didn't want a cup. Her hot chocolate then dispensed itself down the drain.
- threw the camera bag over my head instead of passing it to me. (No, the camera wasn't in it at the time, but I wouldn't want to bet that would have stopped her.)
- blew into a drink bottle, splattering her face with Pepsi.