Look at my AVVO Legal Guide on interstate custody cases. You need to get a custody order in NY, and register it in FL. For more details you schedule a brief paid consultation with an attorney who is familiar with the UCCJEA.
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if you have previously acknowledged paternity and you have an order of filiation you can file in the appropriate county in New York where your son lives with his mother a custody/visitation proceeding or alternatively if a Court order exists you may want to pursue a Writ of Habeus Corpus proceeding.
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