Nanny holiday entititlement and what about when you go away?

[history]

Hi all,
I am in the process of employing a nanny as I'm going back to work. One of the best candidates has informed us she has 2 * 2 weeks holiday already booked over the next year, none of which fit into school holidays when we would be going away or taking leave, so obviously we would have to sort out alternative childcare cover for all of those 4 weeks. I can understand that we could just wear this for the first year and then contractually say after year 1 then it's the 50/50 spilt on choice. My question is that when we then go on holiday at the times we choose or take leave she obviously will not be required for work so I'm assuming that it isn't unreasonable to say that she has to take our hols as unpaid leave as she has already used or booked in her whole paid holiday allocation (excluding BH's)? Even if we are in normal 50.50 land and we use leave beyond her 4 weeks and so son;t require her for work - what is good practice - obviously she gets additional leave but would it normally be unpaid? Advice please?!

so history-are you going to employ this nanny?

Thanks for the advice all - have talked about it at second interview and think we've found a way forward that we can all live with for the first year anyway then we go to 50/50 arrangement. The thing is that she does seem to be the best candidate in person and the kids areally warmed to her so although I would prefer someone without the holiday issue actually I want the best person for the kids so trying to choose on that basis - I think that she probably is going to be first on the list to offer it to and then we hope we've made the right choice, am hoping as we are trying v hard to accomodate her (whilst not disadvantaging our own situation any more than that it will be appreciated by nanny!