unless you agreed something specific with regards to holiday in your contract then she pays you full fees.
Otherwise we'd end up with no payment every time granny, uncles and aunts or whoever could help out.
What do your contracts say about holidays? Does it say parents pay full/half/no fee for their own holiday?
I would say to her, our contract is for xxxx, you understand that that means even if he is with his dad you will still need to pay xxxx.
if you do what you've always done, you'll get what you've always got
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