i know guys that carried their kids out in a papoose back scouting. I think its never to early to introduce the great outdoors to a kid. as long as its fun for them and it doesn't become a chore they may stick with it their entire life. meaning the weather needs to be nice and you can't be out there from sun up to sun down. go at their pace so it remains fun for them. their maturity level will tell you when they can start to hunt. mix in firearms, including bb guns, as you feel fit.