I agree that a tab would give you some more room for the list. What you're describing is probably caused by the fact that the new record in PatientF is not saved yet, so you need to save it first. In the FinancialAssistanceListF form add this to the button that opens the FinancialAssistanceF form to enter a new record
Code:
Forms!PatientF.Form.Dirty=False
DoCmd.OpenForm "FinancialAssistanceF", , , acFormAdd
Forms!FinancialAssistanceF!PersonID = Forms!PatientF!PersonID
You haven't showed us the code used on the button on the patient form to open the list; add a Me.Dirty = False there as well.
Cheers,