I tried a 223 many years ago........I am sure it killed every deer I shot. We only found 1 out 3. The one we found ran about 80 yards and piled up. There was not a speck of blood anywhere between the shot location and death location. The other 2 were exactly the same way. NO BLOOD TRAIL at all and we never found um......
I tried a 2 different bullets and still had the same results. If I was gonna use one (223) the only shot I would take is a head or neck. The blood trail from the boiler room is way to inconsistent fo me.
I feel you pain about the kids though....A 223 is very kid friendly. If she has close shots and can hit a head shot I say go for it. If not, get her 243 and good recoil pad. Let her shot it with open sights a few times before adding the pressure of lookin through a scope. She will feel better when the scope does get put on. My 8 year old son weighs 65 lbs and can handle the 243 ok. It just takes a while to get um comfortble to the gun.