My blood type has changed.
I used to be AB, a universal recipient.
Now I'm A, the nerdiest blood type.
My blood, my spit, my skin cells are genetically and chromosomally identical to my sister - so I can frame her for murder if she ever pisses me off!
I am allergic to my cat.
I've never had any allergies in my life. But my sister has allergies, so now I do as well!
But that won't keep me from kitty snuggles!