Just file an amended motion, the worst thing that can happen is the Judge will only hear the original motion for contempt. I believe you have a good chance the Court will hear the Amended Motion unless there is a good reason for it not too, such as if the hearing is in a few days and your ex states he or she had no time to prepare an argument for the amended motion.
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My colleague, Ms. Lindquist, has already stated essentially all of that which can be set forth in response to your question based on the rather limited information which has been provided to us. Let me add that I am in no way criticizing your question. It is actually set forth very well; the fact is simply that it is not a question that calls for a response in the form of a treatise. Unlike the pleadings in a case, one does not need to seek leave of court before filing an amendment to a Motion. As an aside, you would lose more time if you proceeded in this fashion, and your former spouse would thereby actually be in a better position, theoretically, to argue that he or she now has even less time to prepare a proper and complete response to the Amended Motion. Like my colleague, I believe it is very likely that the Judge will entertain your Motion, as amended, and I would merely suggest that you file and serve the Amended Motion as quickly as possible and through the most expeditious means possible (e-correspondence for example, along with delivery by first-class U.S. Mail). One further tip, call the Judge's office, and determine by speaking with his or her assistant, whether he or she prefers to have a courtesy copy delivered to his or her chambers, or office, prior to the hearing, and, if so, when, as some request that same be delivered a specified number of days in advance while others actually prefer to be handed a courtesy copy at the time of the hearing. Good luck and best regards, David B. Dohner, Esq.
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My colleagues are right. You don't need to do anything other than to file your amended motion, and it's likely that the judge will hear it as amended, especially if you file your amended motion (and amended notice of hearing) right away. No approval for an amendment to this kind of motion is required. I write only to point out that "makeup time" is required by the statute, so your amendment may be less important than you think. I assume your your motion for contempt is because the other parent "stole" some of your timeshare. In these cases, the judge is supposed to always grant makeup time, though they don't always do that unless you remind them by showing them the statute.
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