5 Going on 50

I have the displeasure at this particular time of having a 5 year old that is going on to the ripe age of 50.  He knows everything and seems to think the world should only be revolving around when he wants something and when he wants to do something.  Leaving B and I in slight despair at his actions.  Every request made to Master 5 is met with resistance, stomping of feet and just flat out rudeness.  Leaving me pondering why people have such a stink about punishing their child. There has been times where i have thought 'if anyone else spoke to me the way Master 5 did, i don't think i would of hesitated in either giving them a tap or kicking them out of my home'.  But as a parent we must politely tell them that their behaviour is not acceptable and continue to love and cherish the world in which they thrive.  Problem with this is that Master 5 is the eldest.  He has another very impressionable Master 3 and Miss 1.5 to follow and repeat his footsteps.  So not only do we now incur Master 5 bad behaviour but we also encounter the other two trying it out for s&^ts and giggles.  Leaving B and I somewhat at the point of contemplating if locking them in a cupboard or leaving them on someones doorstep would be a good idea.  I pose the question to myself every day before i arise 'what will i have to deal with today?'.  Master 5 never fails to show his 'unacceptable' side.  Even as I type i can hear Master 5 rustling through the fridge even though i have already told him twice 'NO'.  This now gives me no choice but to sign off for now and start threatening violence.  Wish me luck.