How do I enter 1099-INT that one of my dependents earned?

The IRS expects the person whose Social Security number appears on the IRS form 1099-INT to report the income.  Do not report the income of your dependent on your personal Federal 1040 income tax return.

 

A dependent of another taxpayer is required to file his or her own tax return if:

 

• Your earned income (money you made by working) exceeds $13,850,
• Your unearned income (interest, dividends, capital gains, etc.) exceeds $1,250,
• Your business or self-employment net income (gross minus expenses) is at least $400,
• Your gross income (earned plus unearned) exceeds the larger of $1,250 or your earned income (up to $13,450) plus $400.

 

But even if your income falls below these filing requirements, the dependent will want to file their own tax return to get a refund of any federal or state taxes withheld from their paychecks.

 

The IRS defines earned income as:

 

• Taxable income you earned as an employee, such as wages, salaries, commissions, and tips,
• Profits from operating your business or farm,
• Long-term disability pay if received before the minimum retirement age,
• Union strike benefits.

 

The IRS defines unearned income as:

 

• Interest, dividend, or investment income,
• Retirement or Social Security income,
• Alimony or child support,
• Unemployment or worker's compensation,
• Gifts, prizes, awards, or winnings,
• Inheritances,
• Income received while incarcerated, even if it involves active work.

See also this TurboTax Help.

 

Depending on the amount and if he has any other income you might need to enter it on your return.  See this article on How to report and pay the Kiddie Tax
https://ttlc.intuit.com/turbotax-support/en-us/help-article/taxation/report-pay-kiddie-tax-return-year/L3eHvp1n4_US_en_US?uid=lst7rs1c