When you add a parent to a student, the first thing that CP attempts to do is search for the parent, based on name and email address. If it finds a match, it will link the existing parent record to the student.
Here’s how you do it:
If the system is able to find a match, the parent will be linked to the student.
If the system was unable to find a match, the page will redisplay requesting you to fill in the remaining information (salutation, address, etc). If you are sure the parent is in CP already, check your spelling of the names and email and re-submit.
Once complete, you can add any additional parents using the same technique. The only difference will be that the address fields will automatically be filled in for subsequent parents based on the address of the first parent added.