I'm glad your son is upstanding. I, however, would never hire your teenaged son and entrust him with the care of my children. Not in this day and age.
Unfortunately, teen boys and parents of teen boys also need to take into account the possibility of FALSE charges of molestation being leveled. It's sad, but in this day and age, no male should ever be alone with any children that are not his own family members; because you never know who is going to say he did what, and the accused will be considered guilty until he can prove his innocence.
Sad, but that's how far we've sunk as a society.
When my kids were small I never had a "babysitter". My friends and I took swapped turns watching the kids - so they were always with an adult.
Now we live in a small neighborhood. The neighbors know my kids and our family. My kids took the Red Cross babysitter class and the experience was good for both my daughter and my son.
They also learned that they didn't make a great deal of money for the level of responsibilty.
My son makes $35-$50 per lawn cutting grass - might take him an hour and a half tops.
If the kids were paid $3 an hour to watch a bunch of small kids they were lucky.
Do the math.
Makes you wonder what we consider important in life.
In this day and age I wouldn't leave my kids with any teenager....mostly we chose not to go out.