I think something may have been overlooked here.
In order to qualify my child as qualifying relative,
You refer to the dependent as "my child" yet reference the "qualifying relative" rules, instead of the "qualifying child" rules. Why?
Was the child under the age of 19 *or* under the age of 24 and a student on Dec 31 of 2019? If yes, it's more likely the child's earned income does not matter. There's other rules, but won't go into it until I understand the discrepancy in your comment in bold type above.
