I did search everywhere for the letter while he was in the shower. I found the envelope in the bin but can't find the letter.
He doesn't drive so it's not a parking ticket.
I've asked him everything....under age sex....which he laughed at and said he's a virgin.....under age drinking....nope, smoking in a no smoking place...no. Trespassing, shoplifting, drugs......no no no.
He just laughs at everything I suggest and tells me to stop worrying as it's 'sorted now'. and what's the point of worrying.
I told him I'll get it out of his best friend later, and he said....no you won't. so I said OK unless one of you tell me you are grounded and Jamie can't stay over any more. So he said he couldn't believe I'd resort to blackmail!
GRRRRRRR
He's such a lovely boy I just can't imagine what it can be, and he usually confides in me about everything.

Well I'll try his friend later! I suppose if it is 'sorted' I can stop worrying, but I'd like to know all the same!

Thanks for letting me get it off my chest here anyway.