Being in possession of a painting that you "reasonably believe" is worth $6000 (or any other amount) does NOT constitute earned income for your child and does NOT qualify your child for a Roth IRA.
Suggest you read the IRS definition of earned income in this reference: https://www.irs.gov/credits-deductions/individuals/earned-income-tax-credit/earned-income
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
