Public Variables on Widget BP children?

So, lets say… I create a widget with text in it. I bind the text so that I can type it in per instance. I pull that widget into another widget. I will see a variable for text where I can chose the text I want. However, what if I want to save this new widget into another widget and retain the ability to type in the text. How do I keep this variable public? Is this where the interface comes in?