Screenwriting : How would you write the scene action for a scene like this...? by Simon Wilkinson

Say you have a scene which starts at a breakfast table with your protagonist, her parents, three brothers and two sisters. The parents are significant characters, as is one of the siblings and the scene develops into a family row between these four - but the other siblings - all young children - have no function except to show that this is a large family (not an important fact - but one that sets a realistic family dynamic). Is it necessary to give these incidental characters names, ages, descriptions? Whilst they are ever-present, they are just background noise. One the one hand it would be easier to ignore them, but to do so would distort the family dynamic - and yet I don't want to wast page space on them... Any suggestions greatly appreciated.