If the only reason he wants joint custody is to not pay child support then joint custody is not a good idea. The courts will always look at the best interest of the minor child. Your son is 4 so you should consider a schedule that will work for him when he goes to school. With your husband's work schedule joint custody may not be the best option for your son. You want your son on a fairly consistent schedule no mater which parent has custody/visitation.
As for your husband walking out and cheating during the course of the marriage you would need to speak with an attorney regarding post separation and alimony.
This information provided is general in nature and does not create an attorney client privilege. Please consult with an attorney to get a more detailed and specific answer to your legal matter.
Talk to a local family law attorney immediately. There are rights you could possibly forfeit and not know it. The presumption in NC is joint legal custody - but physical custody will depend on the best interest of the children. And even if you have 50/50 custody, he could still have to pay child support - that depends on income. Contact an attorney.
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