Applying a client-side filter for child tables in script reports

Hello

When creating a script report, you have a js component with a client side filter. Usually, this looks like this:

frappe.query_reports["Your Report"] = {
  "filters": [
{
        "fieldname":"your_name",
        "label": __("your_doctype"),
        "fieldtype": "your data type",
}]}

However, I cannot apply this method for a child table because child tables aren’t doctypes.
What I’ve found so far, didn’t help in my specific problem. Any tipps?