I have mixed emotions about this. I am married but don't have any kids yet. It is aggravating when a young kid is sitting near me and he or she is screaming, crying, etc. It is especially aggravating when both I and the kid are in first class. My feeling is this: if you have enough money or status on an airline to be able to get your very young child into first class, that's your right. But you should also have the decency to fly coach if you know your kid is a noisy traveller. If you fly first class repeatedly and your child always screams, you should have the decency to realize that you are impeding peoples' ability to enjoy a luxury that they have paid for. You should fly coach next time.

And for those who don't like screaming kids or other loud noises, do as I do. I always travel with good earplugs, i.e. the squishy kind that go all the way into the ear and then expand. They block out most noises. Then I put on noise reducing earphones and I can't hear much of anything. But these don't eliminate all noise. I would still be able to hear a screaming baby if he were a few feet away. Then, my only resort is to look at the offending parent and make them feel bad.