That's a good one,
I have 5 daughters whom all have been around with me hunting since they were old enough to watch deer(around 4 or so) and we go out in the fields and watch the new fawns play as well as the others.
We watch hunting shows the times we aren't hunting, and each one of them are a excellent shot and ethical hunter,the youngest being 12yrs old.
I explain to them that it is our way(we are Native American Indian) to respect and to control the populations of the deer that our Creator has given us for food,they understand that and except it. At 3 and 4 years old they have watched me skin and butcher deer in our barn.I don't believe that this "de-sensitizes" them as much as it helps them understand we only kill them for food when the seasons permit.
Otherwise, we love to grab a couple of peanut butter and Jelly sandwiches and go to the fields and watch them play,until a big one comes out and they tell me "That's the one we need for the freezer!!"