Sign Language?

My son is doing sign language, but no one has taught it to him.

What the heck!?!

The other day Danny started signing "more," when I asked him what he wanted when he was signing he said "more." Now he is signing "eat!" I am so excited, but also wondering where he picked this up from!! I need to go out and get a toddler sign book so I can help nurture this awesome thing he is doing. I can't get over how smart kids are!!