theological questions

Erik and I have been role playing the last couple weeks. We'll pretend we're someone else. He'll want to pretend to be someone we saw at the park or a Sesame Street character. Sometimes he wants me to be a different one, sometimes we are the same character. Last night I asked if he was ready to pray to God. He said his prayers and then wanted to pretend he was God! I must admit, it made me uncomfortable when he said "I'm God" even though I knew to him it was no different from pretending he's Elmo. It just feels strange to hear him say he's God, or that I'm God. Then he asked me "who's God". Oh boy. Later, I wished I could use God's reply to Moses "I am" and just say "God is". But that wouldn't satisfy a two year old. So I told him God was our friend, God made us and God loves us. I mean, other than describing God, what else can I say?