The family can expect light housework from the au pair. This does not include ironing of difficult pieces of laundry like blouses.
Spring cleaning (no matter in which season it takes place) does not belong to that either. If the au pair shall be responsible for the laundry, this should be restricted to hanging out the clothes to dry, folding and ironing. The sorting of dirty underwear is not the task of the au pair and neither is the cleaning of the toilets unless the au pair is the only person who uses this toilet.
Many au pairs do not know how to cook. If this will be necessary in your household, you should clear this out in advance.