I really wouldn't care much about noise on a bus (though it's been more than 10 years since i've been on a peasant carrier), kids are kids, they moan and whine so what?
Now if kids hassle my kids or are just generally rude or abusive to me or my family i go round their house and ask for their dad, if they get lippy you can justifiably slap them about a bit.
Much the same as if a bird gets gobby in the pub, i just tell em to shut up or i'll slap their boyfriend/husband, works wonders.
i did this once, turned out her BF was a brick shithouse. Didn't do it again