@flibbits**
**I read your post how you parent it and there is a mistake. You cannot parent prop by figure parenting window and that is why you don't see your human character in there. More over if you click in that window on one of your props then the Change Parent from Object menu will be disabled.
Follow this:

1. load whatever you need (human and robin clothes)
2. select 1 prop (ie. mask)**
3. go to menu: Object>Change Parent and choose the head of your human
   **3a. if the prop is selected you can also use set parent button in properties window

I really hope that was a problem:)
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