Relocation is not about having substantial info "against" the other parent . . . it requires proof of a material advantage to the moving parent as well as to the child, and then a number of factors come into play to determine if the move is in the child's best interests. A major consideration is what visitation will be available to the non-moving parent that preserves the parent/child relationship. If your ex will not agree to allow you to relocate with the child, you need to file a motion, and I highly recommend you at least consult with an attorney before doing so as your motion must meet the legal requirements to be appropriately considered by the court.
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Because you have primary custody, you must show that you have a sensible good faith reason to move and that there is "reasonable alternative visitation available. A sensible good faith reason is a new job, availablitiy of family support, a new spouse or anything else that would provide you and the child a benefit over Clark County. Reasonable alternative visitation depends on what his current visitation is. Usually the child will spend 8-10 weeks in the summer here, each Spring Break and alternating Thanksgiving and 1/2 of Xmas. You need to be prepared for such an order because even though he may be a less than stellar parent, Judges will give him the most time available because he is losing the benefit of weekly contact. What you have on him may impact the visitation schedule. You also need to be prepared to have your child support reduced by the transportation costs associated with your move.
You should put together a proposal to him asking for his permission in writing and giving him some consideration. When you recognize that a relocation trial could cost 25k and up, his agreement to allow the move is certainly worth a reduction in support or other financial consideration.
The standard that a primary physical custodian must meet to relocate out of state with a child boils down to a good faith basis to relocate and can you work out the visitation. There are other factors, but it boils down to just those factors.
Relocation for a primary custodian is mainly about the primary custodian, not the other parent. If the other parent is a perfectly fit parent, you should be able to relocate without saying anything negative about the other parent so long as you meet the relocation standard. If the other parent is a disaster, then your case is easier.
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