I have a question regarding the multiplicity setting. If I have a child Address
object that holds data for multiple parents, like Customer, Vendor, etc.
What is the multiplicity setting of the Parent?

Assume that an Address cannot exist without a Parent. In that case, a multiplicity
setting of 0 on all parents would seem to mean that an Address can exist
without a parent. I think the multiplicity setting should be 1. Arguements
against that say that would mean that there has to be a record in each parent
table for every address record, which it not the case either, the Customer
parent would only point to customer related address records, not all address

What is correct?