If the court ordered the payment of day care and the ex wife is back in court for the issue of back child support, the court can also address the issue of back day care at that time. Generally child care is a component of child support and therefore would be under the jurisdiction of family court.
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This question really addresses 2 separate, but related issues: 1) Does he have to pay for day care? and 2) If so, does he have to pay it to you?. I agree with my colleague that the family court has resolved the first issue by ordering him to pay for half of day care. As for the second issue, there are several contract related theories that will allow you to recover at least the reasonable value of your services based on your prior course of dealings with your ex son-in-law. Verbal contracts are valid in California, just more difficult to prove. A consultation with a business attorney can assist you with assessing the viability and strategy of a possible small claims action.
This is general information and not meant as specific legal advice for any particular situation.
I agree with my colleague that the more efficient way of handling this is when your daughter is back in court re support, not in an independent action in small claims court.
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