at what age?

I get so many emails about our Delaware Marathon. Course questions, time limits, water and gator aid stops, parking. On and on it goes. I always answer back in a timely fashion. But one email I really had to think about and in fact could not make a decision right away on was from a parent asking if their 14 year old daughter could run our marathon. I forwarded the email to operations director Joel Schiller. Joel emailed the parents asking if their daughter has run any long distances. They emailed back "only a few 5k in the 22:55 range and has run a training run of 12 miles". But they wrote that she would train and run our marathon with her father in approx. 5 hours. We have had a 16 year old participate in our marathon but never one this age. Even with a parents signature I just did not feel that we should allow this young girl to run the distance. Joel and I agreed that the half marathon distance would be ok or the 4 person relay. Joel wrote back a nice note to the parents explaining our decision. Just curious......if you were a race director for a full 26.2 mile marathon would you have accepted her entry?