I think that you really used the vignette style to advantage here - my favorite out of the three was the second. I'd like it if you developed it a bit more, since you seemed to be hinting at Peter's (naturally) outdated social views, and the deep difference between boys and girls that children often feel. The third vignette actually goes a bit over long - I might edit out some things and clarify more why Peter's crying. I thought the first vignette was solid, but you the rhyme between 'sun' and 'fun' is a bit jarring.

More mermaids!

I suggest a word! Inevitably.

:D And I liked it! Good job!