Yesterday I was at the NGO *A lounge waiting for my NGO-SFO flight. There was a couple with a kid I guess around 3yo running around a bit, but not screaming. The man seem to be incouraging it. I was thinking "I hope I am not going to be sitting near them." While waiting for boarding I heard the man say "I think I have got him tired out." Sure enough, except for just one short time the kid was quiet and slept the whole way. I was only 3 rows away from them.
A great way for them to handle it.