Hi H.,
My son had that exact surgery done at about 10 months old. He is now a perfectly healthy almost 6yr old (9 more days til his b-day).
It's a genetic thing in my family tree - my brother had it & my maternal grandfather had it as well. All 3 of them had the surgery & they're all doing fine.
I remember when my son had it done - the absolute WORST part was him getting the anesthesia - I was holding him in my arms when they put the mask on him to breathe in (bubble gum flavor) and he did fine - no fussing/fighting ... he was actually pulling the mask tighter to his mouth b/c of the taste. anyways, when it finally kicked in, his body went completely limp (almost like he died in my arms) that was the creepiest part - thankfully, i'm very strong emotionally & can handle pretty 'tough' situations, but if my husband had been the one in there w/him, he would've come out crying.
Otherwise, ofcourse you're anxious during the surgery. But it will all be fine. Make sure, if it's possible, to have someone other than your spouse go with you. It helps w/keeping small talk going during the wait. I was fortunant to have both my mother & aunt with us, and just being able to sit & talk, really eased my mind during the surgery.
As far as recovery went. Most kids are resilliant. My son was very mellow. No crying/fussing/nothing, he did awesome. That was the first time in a long time that he would just let me hold him (when we got home) to read & watch a movie & I fed him while he was on my lap (we did chicken rice soup - goes down easy, warm for the belly & tasty). He fell asleep & the very next day he was running around like nothing happened. He did awesome. I had to restrain him from stretching his groin area due to running, jumping, falling, straddling things, etc. But he healed beautifully. The scars are barely there now, and he's happy & healthy & everything (as far as we know) is in working order. =0)
the tylenol w/codeine is great. helps them sleep later too, he'll be able to settle down & get comfy w/o too much discomfort & have a good night's sleep.
I know that there really is nothing anyone can say until you've gone through it & you see with your own eyes that your child is ok & it's all said & done with. But just know that it is a common surgery & i'm pretty sure he'll do fine.
Good luck & God Bless!