I like the concept, funny. I wonder if choosing a different point of view could have suggested a relationship between big one and little one ('mummy's little girl" or something to that effect). Good idea.
I see where you are going with this one, but too much of a stretch to the challenge topic for me, sorry. My view is that the challenge is using the word "baby" as a noun, not an adjective. Therefore, I will be knocking a couple of points off for my perception that this DNMC.