He has it planned, but is it written down? See if you can get him to get all his ideas in writing, and then perhaps a storyboard (comic book structure) of a typical gameplay experience.

There are many homebrew programs for writing the software, but see if you can get him to get all his ideas on paper, so that your sister can check with her contacts and see which one is best.

I'll keep looking if he just plain won't write it down.

Trinity

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