It’s not unusual for a housekeeper to help with the household’s children, preparing meals, walking them to school, but what about babysitting?
Have you given any consideration as to how this element is to be handled. If you go out in the evening for four or five hours, would you expect to give your housekeeper time off in lieu or would you expect them to just extend their day and say: ”Yes, that’s fine.” More to the point, how will your housekeeper react?
They may agree to babysit, but may ask expect to be paid for the extra hours; on the other hand, they may be flexible enough to just fit in with your needs.
Either way, it’s an issue that is best resolved before the request is made, so why not build it into the contract of employment that you issue, and then everyone knows where they stand?