When Form 8615 must be filed. Form 8615 must be filed for a child if all of the following statements are true:
The child's unearned income was more than $2,100.
The child is required to file a return for 2016.
The child either:
Was under age 18 at the end of the year,
Was age 18 at the end of the year and didn't have earned income that was more than half of his or her support, or
Was a full-time student at least age 19 and under age 24 at the end of 2016 and didn't have earned income that was more than half of the child's support.
At least one of the child's parents was alive at the end of 2016.
The child doesn't file a joint return for 2016.