RE: My 7 year old's first deer- we can't find it???
Ok first thing first. If he can handle a 22-250 he can handle a 20 gauge or a muzzle loader or even a 243. Just something to think of for the future.
Anyway. go to where you found the blood. Track backwards towards the shot. I've seen that many times the spot you think the shot isn't realy where they were standing. You may be supprized if track backwards to the shot. You should find some hair etc. Then track the other way. I personaly would never have gone after him untill I let him sit a while. Of course I don't remember you mentioning how long you waited.
Also where did he hit the deer?