Who's on first?

Trying to teach Ally to say "I" instead of "me."

Ally: "Me want a drink of water."
Me: "Say 'I'."
Ally: "Ally" (the way she says "Ally" it sounds an awful lot like "I").
Me: "No, 'I' "
Ally: "I."
Me: "Ok, now I want a drink of water."
Ally: "No, ME! Me want a drink of water!"
Me: "No, you say I. I want a drink of water."
Ally: "No, ME! Me is thirsty. Ally (not I) wants a drink of water."

We have some work to do.