I let her operate my camera...One of my lenses cost more than the P3A and P3P combined.
I let her fire some of my guns (the ones appropriate to her size and stature). Some of them cost as much as the P3P and can kill far more reliably than the drone can.
I, of course, let them fly the drone too.
Of course none of those things occurred without proper training and watchful supervision. And none of those things occurred without me being completely confident she understood the risks involved and I felt she was capable of operating the equipment in question.
I was 6 when I pulled my first trigger and dad was there. I was 8 when I finally soloed in my first RC plane and dad was there. He was a range instructor with the USAF. He was also a pilot in the USAF as well (medical grounding). He was fully capable of instructing me as well as supervising the activity.
I don't see a problem here. The parent (or responsible adult) must make extreme effort to insure that the child is both capable mechanically (ie can reach the controls) and mentally ready to do whatever you intend for them to do. If your gut says they aren't ready, they aren't ready. If anything in you has any reservation at all, they are not ready and neither are you. You must be 100% ready too. You must be confident, know what you are doing and be able and ready to take control of the situation at a moment's notice. Inform the child AHEAD of time, what is going to happen if things go wrong. The last thing they need in an emergency situation is more surprise. Give them simple instructions that are easily understood which will allow you to regain control of whatever it is they are operating, be it a camera, a gun or a drone.
That said, if you are a new pilot, gun owner or photographer, you have no business trying to teach a kid while you are not learned yourself.
With all the video games kids play now (opposed to when I was a kid, there were none), I think you will be rather surprised at how easily they can pick up the controller and begin flying. There isn't much difference in the controls on the drone than the controls on an Xbox or PlayStation controller.
I initially took off and landed the first couple flights for each girl. I took it up to about 20' and handed them the controls. I had already gone over the functions but I did it again. This time with the drone in the air and their hands on the sticks. I operated the controls by moving their thumbs and allowed them to feel what was needed on the sticks as well as see what the drone did. In a matter of minutes they were flying around and controlling it just fine. I let them take off and land after two good flights each as I was confident at that point they could handle it.