Some deer are more scent conscious than others. You can get away with a lot more scent issues around more urban scent accustomed deer than you can with deep woods deer. I've had big woods bucks walk up to my track, do a 180 and I never saw that track again the rest of that deer season. As was mentioned earlier, getting up way higher than any 9 year old should be will either blow over the top of the deer or be more dispersed Winds swirl and deer don't always walk nose into the prevailing wind or all the deer would be up in the North West somewhere. You can probably catch a few cross wind, so late in the season you might get sniffed, but it won't wreck the spot long term. A 9 year old just wants to be out there with dad for the experience and a deer should be a bonus.
