Bonta's poem is a short run of pity, each line starting with the word "poor." The speaker pities a child, a beast, the wind, the water, and a wife, and the list keeps widening, so that people, animals, and even the elements all seem to be suffering together.
The title promises a ballad about a bastard, but the poem never tells a story. Instead we get small, broken glimpses: a child who "knows what war" is, a beast that throws away its friends and "everything that is good," a wife dragged into court. Judging by these images, the poem may be about shame, family conflict, and the damage people do to one another, though it leaves the details unsaid.
The mood is bleak but oddly tender. The repeated "poor" sounds like a sigh or a mournful chant. The speaker doesn't seem angry so much as weary, looking at a world where everyone, guilty or not, deserves some sympathy.