No attitude here...I think there are greater dangers in this world than a kid being 10 feet under water. I can show you tons of evidence that these dangers exist....and would be very accepting to evidence that there is danger to kids diving at 10 feet of water, but I have not seen any yet. I am certainly not above being proven wrong and I completely respect your opinion, whether it be professional or personal.
I don't know of any empirical evidence which I could cite along the lines of "If a child spends x minutes at x feet, they will sustain x injury." Likewise, I can't say an adult diving for x minutes at x feet will develop DCS. There is a danger in each case, but that danger needs to be acknowledged and steps should be taken to avoid issues.
There's a lot we don't know about the effects of pressure on growing bodies. There's also a lot we don't know about the effects of pressure on fetal units. In terms of liability, I'm heavily invested in the safety of each and while there are greater potential hazards out there, it does not diminish the risks associated with SCUBA. Should I disregard the potential and unknown risks to a fetus because second hand smoke, alcohol, drugs, trauma and other prenatal risks exist?
If we are talking about 10' depths, I'd agree there is little cause for concern, but I've never certified a kid who was planning on only diving to 10'. When I do take on a kid, I look at the person that kid will be diving with. If they have the attitude that it's no big deal, I educate them. If they still don't appreciate the risks they are subjecting their kid to, I won't certify the kid.
It takes a fairly mature kid to be a competent diver, but they are not what I would consider to be a solid buddy. The parental unit needs to look at their child in much the same way I look at a student.