Test for instance then do something

Hi there,

Wondering if anyone knows if there is a way to test to see if an instance is on the stage, if it is, then do something - else if do something else.

I have added an instance called popInfo to the stage and I want to test for it in my onHover State of a button - so if popInfo is on the stage it disables the onHover otherwise enable it.

Is that something that is do-able?