Quick answer
The support order or agreement may address costs beyond the monthly support amount.
Do now
Read the expense-sharing terms, including approval and reimbursement requirements. Collect invoices, insurance explanations of benefits, proof of payment, and dated requests. Separate urgent treatment decisions from later reimbursement disputes. Ask about modification or enforcement if the existing order does not fit current needs.
Watch for
An expense is not automatically reimbursable just because it benefits a child. Do not delay urgent medical care while arguing over payment.
Official sources
NJ Courts — FD modification application packet, NY Courts — Starting a Child Support Case, DC Courts — Parentage and Child Support Branch.