A childhood belief about imaginary friends

When my sis and I were younger, we would play make-believe mermaids. One day one of our mermaids was having a baby, so we had a lengthy discussion on mermaid reproduction. Obviously they couldn't have a baby the "normal" way, pooping one out (lol- I don't know why so many people believed this), because they had no legs. (Of course we had fish and had seen them poo, but...) So it would have to come out their mouths, as that's the only other way to get something out of their stomach. I said they must have vomited them up, and she agreed, but we decided that was way too disgusting. They didn't lay eggs like fish because they were half-people, so because they were magic they could burp up a bubble with the baby inside (it would grow in the bubble, after it came out of her mouth). Never looked at bubbles in the same way again. We really elaborated on this, and decided that after it started to grow she could sing a magic song and decide how it would look and what age it would be when the bubble popped, if she just wanted to skip it being a baby altogether and have an 8-year-old.