My colleague is correct, and the process is a bit complicated. I highly recommend working through an attorney experienced in these types of matters to minimize the time spent and the risk of being denied in the court system.
Responses are for general information purposes only, and are based on the extremely limited facts given. A consultation with an attorney experienced in the area of law(s) indicated in the question is highly recommended. Information and advice given here should not be relied upon for any final action or decision, as the information is limited by its nature to the question asked and the fact(s) presented in that question. THIS RESPONSE DOES NOT CREATE AN ATTORNEY/CLIENT RELATIONSHIP, particularly considering that the names of the parties are unknown.
It would appear from the facts provided, that Nevada is now the "home state" of the child. While the domestication of the California custody order is fairly simple, just because the child and both parents and the child live in the same jurisdiction does not mean that you can easily change the custodial designation from full (or primary) to joint. There are not enough facts in your question to determine if your reasons for the change are sufficient to meet tha applicable legal standard. I would suggest that once you domesticate the California order, and know who your judge is, that you discuss your options with an experienced practicioner. At the very least, you are likely to be able to increase your timeshare as a result of the geographical change and obtain an order more appropriate to the current facts.
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