I also agree that it's a great idea to have Reese interact with Jenny in an "alpha" way, by feeding her or practicing obedience skills and what not.
I have my older boys, 12, 11 and 8, walk the dogs with me. That way they can learn proper handling with me by their side. Zeus tends to try to see what he can get away with from my 8 year old. Zeus outweighs him by a good 30 lbs!
Zach's a tough kid though, and is learning quickly how to maintain control. (We watch a lot of Dog Whisperer together, too!
) They've also been practicing sit and stays with them in preperation for the TDI test, which has been a big help when I'm working nights and trying to get sleep during the daytime.
We even involve my 3 year old with training by letting him give treats for sitting. I have to pick him up and hold him higher than the dogs so they'll notice him, but he just loves yelling "sit" at them and they love the treats, so everyone's happy!
I don't think any of this would prevent a completely accidental reaction bite, which seems to be what happened with Jenny, but it does help them build a good relationship and mutual respect.