This is the information provided to us by our very reliable and an amazing player April Evans.
Now according to April in her own words
"
ok I found out this info....
The Turkey Costume is a "secret" surprise after you have 300 dishes put into your thanksgiving table, and when you post to the feed you don't share the costume, you share a regular turkey. Also i opened one of those Harvest boxes and got a thing called Double the size of my Avatar when I used theres some sort of Glitch and my avatar went ghosted......just thought I would share this info for anyone who dont know :D Also when you get the Harvest mystery boxes in your Thanksgiving table *redeem 10 dishes for it* then open that Box it goes torwards your THEY OF Mystery box ribbon this may be a glitch so hurry get your ribbons on that before its fixed !!"
I am sharing this information with her permission.
Thank you April for your valuable information and time.