Nice to see you here.

I like the pictures evoked in this poem.

I liked the pairs of lines. Placing two parallel lines against each other over and over will create a kind of music, like the kind we often hear in Old Testament poetry. I thought at first the rhythm just came from those juxtapositions, but then I noticed you also gave each line four accents, which I think is cool.

I think it also works to close up the poem by having that refrain line "One little" come closer together a few times. Also I like recapping the line "One little cry." Maybe you should reprise a couple more lines from earlier.

But I would recommend creating a new ending. Perhaps something else sad but not a child's death. I am not at all against poetry about death but especially since the death of any child is such an emotional punch, I feel like the poem should either be clearly about it from the beginning or would need more build up.

Think of movies and books that build up to the death of a young person. Dickens invests you in the question of whether Tiny Tim will live or die or not. Louisa May Alcott has a novel's amount of time to set you up for ripping your heart out with Beth.

Or on the other hand think of Job, sorrow comes very suddenly (almost the definition of out of the blue) but right at the beginning and you have the rest of the book to wrestle with it.

But how to deliver an emotional punch in a short poem?

A poem that comes to mind is Whitman's O Captain! My Captain! In three stanzas he can't really build up to it -- he briefly sketches what they've passed through and then finishes the first stanza with the Captain lying dead. The contrast between the celebratory throng on the shore and the mourning on the ship gives a pang throughout the poem; also being an allegory on Lincoln's death, it has the advantage of tying into all our feeling about Lincoln.
https://www.poetryfoundation.org/poems/45474/o-captain-my-captain

Another short poem that comes to mind is Goethe's Erlkönig. Only 8 stanzas, but it builds in intensity from the beginning which makes it be able to deliver its punchline (not a funny punchline).

https://en.wikipedia.org/wiki/Erlk\%C3\%B6nig_(Goethe)

If you want a sad end though, sometimes less is more; something painful, but not as painful as death will sometimes be more deeply felt, because it won't be felt as such an extreme and sudden escalation, or as just an obligatory ending verse.

Anyway, I like the poem. I like your diction for this story -- it's fittingly simple but not babyish.