Hey Evan...
Your logic is correct. You can't add items to a display that doesn't exist. That's like mailing a letter to a construction site where houses will be built later on. If you want to know the number of bedrooms in each house on the street, you'll have to wait until it's constructed.
Is there a reason you're doing these actions separately?
You might want to take this step to map out your logic in your functions. From the code that you've posted (in this thread and elsewhere), I think you're falling into a trap of making functions and function calls highly specialized.
There is no real way to do what you want. And, if you think about the situation, why would there be? You shouldn't be attaching properties to non-existent objects. So, if you want hello_mc to exist after clicking a button, create that event listener and within it's callback function, add hello_mc to the display last and then change the properties of the text object.
If the properties will be changing before the item is in the display list, create the object but don't add it to the display list until it's required.
Code:
var movieclip:Movieclip = new Movieclip();
still creates the movieclip object. It's not visible as yet, but it's properties are available.
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