Who is a Qualifying Child?

 

A qualifying child is a child who is your son, daughter,stepchild, foster child, brother, sister, stepbrother, stepsister, half brother, half sister, or a descendant (A descendant is your grandchild, niece or nephew)

And was 

Under age 19 at the end of 2019 and younger than the Taxpayer or Taxpayer spouse if they are filing jointly

Or 

Under age 24 at the end of 2019, a student and younger than the Taxpayer or Taxpayer spouse, if filing jointly 

Or

Any age and Permanently and totally disable

And

Who did contribute over half of his or her own support for 2019

And

Who is not filing a joint Tax return for 2019

Or 

Is filing a joint return for 2019 only to claim a refund of withheld income tax or estimated tax paid

And

Who lived with the Taxpayer for more than half of 2019.