Does anyone know if you can link a subform based on another subform?

My problem is both subforms are linked together with the main form based on one field which is the sales week. Then the first subform has invoice numbers that match to the second subform. I would like the records in my second subform to show for the particular sales week and only those invoice numbers that appear in the second subform.

Is this possible????
Thanks,
Terri Hodkins

Make the second subform a subform of the first subform.