You mentioned that your child has an UTMA account which has earned significant income. TurboTax should ask the appropriate questions about the child's form 1099 (meaning the income is reported under the child's Social Security number) which may be reporting that income, but if there are proceeds from sales of investments (stocks or funds) that are reported on a 1099-B, then that income cannot be reported on a Form 8814 as part of the parents' return. Only interest, dividends and capital gains distributions earned by a child (reported to the recipient on forms 1099-INT and 1099-DIV) can be reported as part of the parents' return. 1099-B proceeds could require the child file a separate 1040, in which case ALL the child's income should go on that separate tax return and none of it should be reported as part of the parent's return.
