Your chances would be better with an attorney. Within certain time limits, it is possible to move for reconsideration or appeal. If the time limits have passed, child support can be modified, in general, upon a showing of a substantial change in circumstances.
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What do you mean you just found out it was increased? Did the mother file for an adjustment or a modification of child support? Was it done through the Superior Court or through DCS? How old is your child? Why is the grandmother the legal guardian? Do you have any custodial rights? If not, why not?
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