If your non-citizen children meet the IRS definition of a qualifying child, you can claim them on your tax return as a dependent. This rule is the same that applies to children who are citizens. Your child qualifies if all the below apply:
The dependent is your son, daughter, stepchild, foster child, brother, sister, half-sibling, step-sibling, an adopted child or a descendant of one of these people such as a grandchild. Both biological and adopted children are treated the same.
On the final day of the year your child is either under the age of 19, a student enrolled full-time under the age of 24 or they are permanently and totally disabled.
The dependent lived with you for more than half of the year.
You provided over half the financial support of the dependent throughout the year.
Your child did not file a joint return with their spouse, if they are married, except only the claim a refund of taxes withheld or estimated taxes paid.
The child is a U.S. resident alien, U.S. National or a resident of Canada or Mexico.
If your non-citizen child dependent does not have a Social Security number (SSN), you’ll need to obtain an Individual Taxpayer Identification Number (ITIN) from the IRS for him or her.