Where Is Your Tummy?

Ashley has been learning about her body features. Last night, while I was reading her books, the book mentions about mouth, ears and hands. So I decided to quiz Ashley a bit.

"Where is your zui ba (mouth)?"
Ashley pointed to her mouth, and said, "ba, ba, ba..."
"Good job!"

"Where are your er duo (ears)?
Ashley grabbed one of her ears, and I said "great!", then she switched her hands to the other ear.
"That's right! You got two ears! Smart girl!"

"So, where is your bi zi (nose)?
Ashley looked at me a bit confused, hesitated a bit, and pointed to her nose.
"YEAH! That's right! That's your bi zi!"
"bi, bi, bi..." Ashley repeated in excitement.

"Where are your yan jing (eyes)?"
Ashley closed one of her eyes and pointed to it.
"YEEAAH! " I started clapping, and Ashley was so happy and she started jumping up and down.

So I decided to ask her something I haven't taught her.
"Ashley, where is your Du Zi (Tummy)?"
Ashley looked at me very confused and probably was thinking, "What is Du Zi? " But for some reason, she squatted down, and pointed to her butt, "Du, du..."
"Hahahaa, Ashley, that's not your Du Zi, that's your Pi Gu!"