Postscript

I just wanted everyone to know that the PEA kid surfaced and is fine. He appears to be a teenager, alas, but otherwise fine.

I found out that T has saved my old Tube card from 1996, and he has no other photos in his wallet. He carefully explained to me last night that I was supposed to sign it.  ("You see the blank line?") He and F take the tube very seriously, saving their oyster cards from summer to summer so they can add money to the original card, while I have to negotiate the line for a new one every time.
(I probably threw this one over my shoulder at the end of that summer: tube schmube....)

But it's enormously touching that someone took the time to pick it up and save it; and then 20 years later tells me that I still in fact need to sign. I mean it's the rule.