According to http://en.uesp.net/wiki/Lore:Calendar
Second Seed, or May, is the appearance of the Shadow. So I thought I'd give a Happy Birthday shout-out to my fellow shadow-kin, both in game and out. I was planning on doing a hatching RP ceremony (PS4), where I'd place several eggs at the base of the Sithis statue, to see if any would hatch into a new generation of Shadowscales. I was going to roll a die and see what number comes up. The number would be the number of newborn Shadowscales. I hope I can inspire PC players to do something similar, if none hadn't already.
If you'd like, please post your pictures of your Shadowscale(s) and how you plan on spending their (your) birthday. I'll post some pictures of my own of the ceremony. Hopefully it goes well.