It’s unlikely that you’ll be driving in Ireland unless you – or your family – is willing to pay a high insurance premium.
Car insurance in Ireland is taken out for the driver – not for the vehicle as is the case in Germany. Car insurance in Ireland is much more expensive than in Germany, particularly if you are under 25 (as the majority of the Au pairs are). Your own driver’s licence is, in fact, valid in Ireland, but, to drive here, the host family would have to take out special insurance for you – which not many families are prepared to do because of the high cost involved. Driving a car without insurance in Ireland is a crime punishable by severe penalties!