Age to use 'Person's youngest dependent' in Age derived factor not working for all relationship type

Summary:

We are trying to create a derived factor and expect it to be applicable on all dependents when Age to use is set to 'Person's youngest dependent' . But looks like it is working only for relationship type 'child'.

For other relationship type such as legal guardianship, adopted child or child of domestic partner, it is not considering. These relationship types are included under plan->Eligibility-> Allowed dependent or Beneficiary Designees tab as dependents.

Curious to know if any one else has faced similar issue or in case its a bug?

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