How to set user control property from the calling user control?

I have 2 user controls: uc1.ascx and uc2.ascx. Both are placed in the same folder. uc1 needs to load uc2, and set a uc2 property. But I cannot figure out how to set the property. 
In uc2.ascx, I have the public property with getter and setter. 
In uc1.ascx, I do:
UserControl uc2 =  (UserControl) LoadControl("uc2.ascx");
uc2.Property = someValue;  //error - cannot find Property

panel1.Controls.Add(uc2);  //panel1 is a panel in uc1

 
Am I missing something here? Thanks!

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