I've just discovered the latest masterpiece, all over the slate hearth. It's in pink coloured pencil, the slate is an unsealed slab. I'm terrified of making it worse by doing the wrong thing! I've only ever cleaned it by dusting/hoovering.
So what can I use on slate, and if you have any suggestions on how to persuade a 4 yo that her 1 yo brother is not to be trusted with pencils I'd be doubly grateful 