Vivian's Knock- Knock Joke

Vivian wanted to join in while Chris and Sam were telling knock-knock jokes:


Vivian: "knock- knock"
Chris & Sam: "who's there?"
Vivian: "Joe!"
Chris & Sam: "Joe who?"
Vivian: "Joe!"

This went on for several rounds before Sam got frustrated and yelled, "it can't be just Joe, it has to be Joe-something, Viv!"
So the next round was:

Vivian: "knock- knock"
Chris & Sam:  "who's there?"
Vivian: "Joe!"
Chris & Sam:  "Joe who?"
Vivian  "Joe n' auntie!"