A good laugh

We finished our water colour drawing session and was heading to the washroom to wash up. When there, we noticed that some one else is using the washroom. So I told Grace to wait.

Then this conversation took place (again conversation are translated from mandarin; I did not put in the chinese words this time, as some of the words I don't know how it looks like in chinese..hehehe...):

Grace: Who's in there?
Mummy: I think is "shen shen" (aunt)
Grace: What is she doing inside?
Mummy: I don't know.
Grace: What is she doing inside? (a little agitated this time)
Mummy: I don't know,
Grace: (starts to whimper) I'm want to talk (or more of like, I'm trying to talk) to you. Don't say "I don't know"!
Mummy: Dumb

Is this something you get out of a 2 1/2 year-old kid?