20?

My dad's parents sent me a nice birthday card (like they always do) with a little writing from themselves in it and part of it says "Wishing our dear Grandaughter a very special, happy, and fun 20th birthday." I don't blame them for getting my birthday wrong.... they have more than one grandchild... they are getting old I'll just say it... but the bad thing is I think they gave me more money than they usually do because they thought I was turning 2o? Sooo I feel bad? Haha. Bahh.