I use heaters in my shooting houses. Heat up hot chocolate and Vienna sausages and watch deer while me and my boy talk and snack. Shooting houses are sealed up real good. Only time I ever got busted, I opened a window with a buck about 15 yards downwind. Other than that, they never pay a bit of attention to us. I think sealed well with good windows is the key. Best way to keep a kids mind in the game. My boys been going with me since he was 5. Heater is a must.