We had another appointment at the hospital yesterday, and they set a date for Espen's surgery - Monday, September 25th. They really want to do it as soon as possible, and actually moved another kid's surgery back a few weeks, so that Espen could take his spot.
Espen seems fairly calm about the whole thing, but I can see that he's a little freaked out. He makes some comments every now and then. He'll have to be out of school for a week (he doesn't have to stay at the hospital, though), but he doesn't want his teacher to tell the class that he's having surgery until the day of the surgery.