I started taking my kids at 5yrs old including my special needs kids (now that's work). Before that took my God-children from about age 10.
A lot depends on the hunt and your preparation. If you know where you are going and how to hunt it. The kid is not a problem.
I took one son to Wy for antelope and deer at 10 too young for his own tag. 10dys of the best father son trip ever . We hiked 5mi a day with no issues but wearing good gear. For him, he gets cold easily like my wife and mother but we dressed him knowing that.
Went back following year with him and other son with autism. Region C and closer to 20mi a day. At 11 and 13, they could handle much more and were great help getting animals out.
Funny thing with the kids, it's all about the food.
My youngest, 11, and I just did 5 dys of deer last fall. He was my utv chauffeur. We played card games and listened to cool music every night while eating cookies. We popped into town for soda and ice cream. We hiked around 3mi a day in rough country. Most of my pics are of him napping at the top of the mountains when we stopped to glass.
You may never have another chance to do this with your son and he just might return the favor when your old. As much as some of us hate to admit it, money can always buy you a tag so it really isn't your last chance at an elk hunt. Pretty soon it will be him with the tag and you will want to be with him for that event just like he wants to be with you.
I always try to get help (Mom, uncles, friends) so kids could choose to stay in camp or just do evening. I have never been successful at that. Only time it was a problem was trying to deer hunt with 4 kids and 4 rifles. I did not have enough hands and the teenager started acting like one. Now I split up their hunts so no teenager can ruin any hunt but their own.