My child table has ~50 possible values for a required text field. Each parent record has children representing some combination of these text values. Is there a way to set up a dynamic filter for a report on the parents table that would list all these possible values and enable users to filter by parents which are related to child records that contain specific values?
.. building on what Kigsly said above, you van use a Summary Report on the child table to get the result you are looking for. It is also possible to provide a link in the summary report which will take you to the Parent record instead of the children, as your goal is to get to a Parent, I believe.