Dependents must file a tax return and pay taxes if income exceeds set limits. For 2016, a single dependent under age 65 who is not blind must file a return if any of the following applies:
Whether taxes are owed depends on the nature and amount of the income.
On Form 1040X, you may file an amended return within a three-year period to claim a refund or correct a mistake made on an original or previously amended return.