Yes, I'd keep it as brief as possible without losing too much of what you really want to put across. She might get bored half way through if it's too long
. You don't have to have bells and ribbons on it, just give her the facts and the assurance that the Oz issue won't happen again because the circumstances will be different.
It's good if you've written it all down because it's easier to pick through it and cut bits out until your happy with it.
I'm off to bed now and off to Switzerland for a few days tomorrow so I won't be far away from you.
