Pronouns are negotiable in a 3 year old’s vocabulary along with verb tenses, bedtimes, portions, and weather appropriate clothing. Here’s an example of a typical exchange with our daughter in our household:
Nora: “I want Daniel Tiger! I want Daniel Tiger….(whisper) I want Daniel Tiger.”
Self: “Did you pick up your puzzle?”
Nora: “Ya’ aaaare.” (Translation: I did)
It’s like arguing with a drunken Irish dwarf pirate. Everything requires patience, translation, and painkillers.