email – have users inbox be another users folder

I have a folder in my mailbox that I would like to use as another user’s inbox. I need to hire an assistant that will help me only with some specific tasks. All that items related to that task go into my a particular folder. When my new assistant logs in I need for him to ONLY see what is in that folder. How can I accomplish this and/or what options do I have, or is there a better suggestion? The email is hosted on go daddy.

If there is a Linux server that I can build and forward my emails to that server that will give me that option I am ok with it.