i think it should depend on the maturity of the two people involved but the parents should pay attention to what sort of guy he is, making sure there's some sort of birth control involved. personally i'd rather have my one of my daughters sleeping with a 22 year old with protection, than showing up pregnant and not sure who the father is, that situation happens between high school kids, and most parents aren't even aware their children are dating.

besides, i heard if you subtract five years from a man's actual age, you get his real age, that'd put the 22 year old at about 17, that's just about right for her.

but seriously, if her parents have established a strong sense of herself, indepenedence and encouraged her ability to say no to anything she doesn't want to do, i'd be pretty confident in my daughter to put her foot down and say, no way! to anything she wouldn't want to do.

besides something like this will probably fizzle out by summer and she'll be on to the next boy; the 22 year old will be doing 22 year old things and if the parents are really clever, their daughter will have a very busy family summer, visiting out of town family.

i wouldn't worry about a 22 year old, especially if he's a town boy; but anything over ten years, i would develop some serious concern about the age difference.