First, you will have to provide some kind of documentation to show to the FSA provider to get them to release the funds. The FSA trustee can't release funds without due diligence that the expenses are legitimate.
Second, you will need to report the care providers' name, address and SSN on your tax return so that the expenses are qualified on form 2441.
Third, as a result of #2, the IRS will look for matching taxable income on your parent's tax return. Whether or not they owe tax and how much will depend on their other tax facts.
