When TJ was a little boy, not the big strapping three-year-old he is now, he would say Thank You so it sounded like "dick-daw" - John and I still use that every now and then in conversation.
He used to yell "ay-nay" from his crib, when he wanted us to come...again and again, "Ay-NAY!! Ay-NAY!! Ay Nay!" - we never did figure out what it meant or where it came from.
Julia, I'm positive, says "Thank You" when I give her a bottle of milk. "Thank you."
She also yells "Georgia" in the same tone that we do and when we do.
TJ's first word was very clearly "cracker" - I am not entirely convinced that her "real" first word has announced itself as of right now.