If you’re a sole proprietor or a one-member LLC, there’s no FICA tax owed on wages to your child under age 18, and no FUTA under age 21. What’s more your child can earn $6,300 for the year with no income tax. And he or she can fund an IRA or Roth IRA. Caution: Keep good records of hours and work performed. Find more information from the IRS.