A 4 yr old is a small child. A fourteen yr old isn't.
It's an airline. Not a babysitter. How is the parent not to blame for sending him unsupervised? This SHOULD be thrown out of court pretty fast.
No, it shouldn't. If an under age passenger alerts the airline that they are being harassed, the airline has a duty to deal with it. They failed miserably.
Now I will say that the father should have smacked his son on the back of the head and told him to grow some balls.
A 14 year old traveling alone is still an unaccompanied minor, and the airline still has additional responsibilities for the welfare of such passengers. Which is why there is a fee for unaccompanied minors.
Age aside, unwanted sexual advances by a drunk passenger are not something ANY passenger should have to put up with.
I have been on airplanes many many times and have never been sexually harassed by any female passengers.
Come to think of it, I have never had to deal with a frisky woman anywhere at any time. 
Apparently the 14 year old is a stud muffin .. or she is a perv ... or both.
Youth is wasted on the young - B Shaw
I see what you are tying to insinuate here and I have to say that I resent the implication and that you are probably correct. 
In the kids defense, she's probably ugly. Then again, at that age, I probably wouldn't have cared...
Seriously. At 14 I was trying to get in the pants of any girl possible. I probably would have stepped off that plane with a MHC membership and a good buzz.
Some kids have all the luck.
raz-00
I do not understand how an airline today, in this post-9-11 world would permit a passenger to be abusive to a small child," Deutschman said.
It's sexual terrorism I tell you.
Seriously, what does 9-11 have to do with a kid being harassed by a drunk woman? although his gripe sounds legit, he should be punched in the face for associating this with 9-11.