Object diagram: add slot from relationship of this class in class diagram

Hi everyone,

I am quit new to Visual Paradigm, but I have created several diagrams though.
My questions is about modeling a object diagram:

I have more or less finished a class diagram to a specific topic. No I need to
model some situation with this classes in an object diagram. So I started creating several
instance specifications and associate them.
I’ve also added some slots, e.g. an instance of “town” needs a name in the object diagram.
So far nor problems…

But how do I add a slot, lets say “acting mayor” if in my class diagram,
“acting mayor” is defined as its own class and "town aggregates (has-a-) “acting mayor”?

in general words:
So I have these two classes in my class diagram, one aggregating another.
How can the object that owns the other define it in an object diagram?

Thank you!