The father is legally NOT ALLOWED to refuse to pay Child Support.
The Law feels that both parents are responsible for supporting the child they created ...
Yes, take him to Court for Child Support.
If you do not need the money to spend on food, housing, clothing, school FOR YOUR SON, then set up a savings account at the bank for when he turns 18, or 21 or whatever, and deposit the money into that account.
This money is HIS . .not yours. The father owes it to his son.
Your spouse doesn't know what he is talking about.
Child Support is set by your spouse's income, but it doesn't even cover all of what it costs to raise the child. it is designed to be your ex's contribution to the cost of raising your son.
YOU have to earn money to contribute to the cost of raising your son - even with Child Support - as well as 100% of what it costs to support yourself. But you probably know that .. your ex doesn't.