My super-kind boss allowed me the time to knock this up at work for Chris' son. I had designed it in my head as I cycled in and it really wasn't difficult to assemble it.
Choosing the right words was more difficult, but I hope I have got the balance right and that whichever adult picks it up will pass it on to the child. I'm not sticking the envelope down for that very reason, in case an adult wants to vet it first.