I searched:
It depends:
Most important, what did you agree to?
Is there an expectation of vacation pay?
What are your neighbours/friends doing?
What are your country's laws?
How much do you like your nanny?
Is there a reason why you might want to continue paying during a
vacation so that they won't look for another employer? http://parenting.stackexchange.com/questions/2012/do-you-pay-a-