A qualifying child for purposes of the child tax credit is a child who:

Is your son, daughter, stepchild, foster child, brother, sister, stepbrother, stepsister, half brother, half sister, or a descendant of any of them (for example, your grandchild, niece, or nephew),

Was under age 17 at the end of 2015,

Did not provide over half of his or her own support for 2015,

Lived with you for more than half of 2015 (or was born anytime during the year),

Is claimed as a dependent on your return,

Does not file a joint return for the year (or files it only to claim a refund of withheld income tax or estimated tax paid), and

Was a U.S. citizen, a U.S. national, or a U.S. resident alien.