The Candycorn Spring Fairy was a rare drop in the Bobbing for Treats minigame during the Valley of Ebil event in 2013. Although it was created by Gusteon, it is considered an official site color, and not a custom. This color cannot be passed down to offspring.
The Eternal Youth pose was released during the following year's Valley of Ebil event, as the prize for completing one's marshmallow collection.