Yes, she will have to file a tax return and claim the income, her age is of no importance. She will have to pay Self-Employment tax on the income. That will be 15.3% of 92.35% of the $8,200. She has to file and pay that even if she does not owe any ordinary income tax. Personal exemptions/deductions have absolutely on effect on the Self-Employment tax. If you claim the credit you will have to supply her SSN and that will enable the IRS to check her tax return to make sure that she reports the income.