When a new record is created?
1. What previous record? the random record before the new one? The previous serial numbered record? The last value of what record?
2 Greatest value? Last random record value? Value of record after a sort?
1. Relationships will be 1 to many in the order: 1 Patient (person) > many Prescriptions > many Records.
2. Once a patient is chosen, any new Record should follow the previous dated Record for the last dated Prescription.
3. Soring Prescription and Record would always be by date.
Your Relationship should be:
Patients::__pkPatientID = Prescriptions::_fkPatientID
For help with this notation, see: Common Forum Relationship and Field Notations Explained
In which case, a sorted portal or a sorted relationship that sorts by prescription date in descending order will list the most recent Prescriptions first if you place a portal to Prescriptions on your Patients layout.