Why?...Why?...Why?

Scene: It's bedtime for Buttons and we're reading The Big Red Barn.
Backstory: Buttons is very interactive with story reading.

Buttons: What's that Mama? (Pointing to the cow's udders.)
Me: Remember when we talked about how some mommies breast feed babies and some mommies and daddies give their baby special milk from a store?
Buttons nods.
Me: Well, the baby cows drink from these and they're called udders.
Buttons: Why?
Me: Because that's how the mothers give milk to their babies. (I'm thinking to myself "was she wondering about why they're called udders?")
Buttons: Why?
Me: Um, because their milk is stored in there.
Buttons: Why?
Me: You ask very good questions Buttons. I think we should finish the book since it's bedtime now.

Notes: This scene was actually condensed. I'm so excited that she is interested in everything, but it hurts my brain sometimes. I hope I can keep up with her. A friend told me she will turn the question back to her daughter by saying "what do you think" and that has worked pretty well for me on many occasions. However, I have a feeling she'll be asking more in depth questions about babies soon since a couple of friends are having babies and she's very interested. I'm not into stork folktales and I label body parts with appropriate names but it will be interesting when I try to give the 2 year old version of the birds and the bees and I'm met with a thousand why's.

Update: I was reading over this post again this morning (May 4) to check for spelling errors. Buttons saw the cow picture and became very excited.
Buttons: Look mama, cows!
Me: Yes, cows.
Buttons: There are two cows.
Me: Yes there are.
Buttons: What are they doing mama?
Me: Just standing there.
Buttons: Why?