I joined on the 1st of December, 2012, meaning the first pet I knew the rarity of would be the December 18th ones. It just so happened that I received my first rare on that day (as I know you can also receive uncommons) from the Christmas of 2009.
I've kept her since given she has always meant the world to me. She is my first after all! I am quite sad to say that I did receive a lot of trades back then trying to underpay for her, as they saw I was new and an easy target. While it's allowed, it does sadden me to this day.