I'm sorry to hear of your wife's threats.
It is not necessary in New York for there to be a separation agreement
in force for a custodial parent
to seek child support from the other parent. The court will look at the relative incomes of each parent in determining if, and how much child support is owed. However, your wife would have to get a court order of support before you will be legally obligated to pay her any child support.
Additionally, there is no law that provides that a father may not have primary custody of his children. In fact many fathers do have primary custody. You may seek custody through the court system. Based on the ages of your children, the 15, 16 and 17 year olds will likely have a great deal to say about where they will be primarily living---and if they choose to live with you when not in school, the court will likely go along with that if it finds it to be in their best interests. The 13 year old is bit young for the court to consider their opinion strongly, but if the three older children choose you, I would not be surprised to see the court award you custody of your youngest child.
And, if your wife happens to be awarded custody of one or more of the children, you could also ask the court for an order preventing your wife from relocating the children with out the permission of the court, and this would likely be granted as well.
I wish you and your children the best in 2010.
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