it has been said that young children do not know when to say they feel bad at altitude, or describe what they feel in terms that we can figure out what they are saying. Duh, same for adults.
Best way to prepare is to do some long trail and altitude exposure ( 2 topics) beforehand to see how he likes it.
Does he get the same pleasure of going up that you do? I have a friend whose 3 kids were on-the-go gymnasts with endless energy. Put them on a mountain trail, not even high altitude, and they could not push unwilling flesh up the hill for more than an hour. Key word here, liking it. You gotta like it. This comes before getting in shape, getting acclimatized, etc. Only way -go find out.
With my younger son at age 10, we attempted Whitney, and "failed." He had plenty of mountain enjoyment experience beforehand, but not above 10,000 ft. He had the enjoyment and willingness, but was not a fast acclimatizer. Only one way to find out. We did.
EDIT: Your question 'what is AMS?' indicates you have a lot of homework to do. Please study up. One place to start is the Feature topics "Orientation notes for Whitney first timers" on this website
Edited by Harvey Lankford (04/19/16 06:07 PM)