Device Activity Report for multiple children

How can I differentiate between multiple children in order to display screentime data to the user separately for a parent with multiple children? As far as I can see, the options are .children, and .all? I understand I can retrieve some info from within the extension so I can group data separately, but is there any way to reliably filter between different children from within my app, say using a DeviceActivityFilter?

Many thanks!

Device Activity Report for multiple children
 
 
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