What will we name our baby?

Jack and I were talking about the baby the other day. He says things like, "Baby is born soon. At the hospital." and "I'm a Big Brother!". So I asked him if he knew what the baby's name was going to be. He stared at me, so I said, "What about Ivy? I think we are going to name our baby Ivy." Jack giggled like it was a ridiculous name for a baby. He laughs and says, "No IB!". So I ask him "What do you want to name the baby?". He said, "Sun".