I was really impressed by this poem. It's a powerful and emotive look at a Potterverse issue that I find easy to overlook. When fanfiction almost always focuses on those with magic, you don't tend to think about those who weren't lucky enough to be born with it. The picture you painted of squib children isn't something I will forget easily.
The first thing that grabbed my attention was your use of the direct address.”Dear children” seems like such an innocuous, almost sweet title, but from the first line the poem was anything but. Because you were talking to the children in question, I found that their situation felt a lot more real, a reminder that, in canon, there really were children in this situation. In the five lines where you used that technique, I was imagining actual children constantly, considering them in a lot more detail because you were always talking to them. The focus was completely on them, and I thought that was really powerful.
I think my favourite part of this poem was when you used the metaphor of the imprisoned children as plants. It created a really clear picture in my mind and really helped to bring the scenario to life. When you described them as “stunted seedlings”, I felt suddenly aware of the physical suffering that these children might go through, as well as the emotional hardship. That combined with the phrase “kept from light of day” gave me chills. Confining a child to the house out of shame is so cruel, and it's an image that really got to me.
Another things that impressed me about this poem was the way it sounded. Part of that was, of course, because of your use of sonnet form. I thought you handled the strict rhythm and rhyme really well; it felt very natural and added to the poignancy of the poem. However, it was more than that. For example, the alliterative “s” sounds in the first line set up the atmosphere of the poem really effectively. It was kind of sad and soft sounding, just right for the subject matter, I thought.
When I read a poem, I don't often find myself thinking about characters, but I was intrigued by the thought of your narrator in this poem, because clearly there was someone thinking. I don't suppose you had a character in mind to narrate, but I felt like the poem had a very clear voice. Whoever it was, their anger about this subject came across strongly. In particular, I loved that I could just imagine the ire dripping from their voice when you wrote '"sympathy"'.
The last thing I'd like to mention is that I found myself connecting certain canon characters and events to this poem. In particular, the images of a children locked up for their own good, deprived of normal life and unable to ever act evoked Ariana's memory for me. I think that remembering her only increased my pity for the other children you write about, because we know that she must have suffered greatly. The other character I found myself thinking of was Neville. We know that the Longbottoms, a family I think of as some of the “good” purebloods, were very worried by the idea that Neville might not be magical, and Neville talked about the things that they did to try and make his magic appear. If his family did these things, what might a family like the Malfoys do? It's not a pleasant thought.
I can hardly say I enjoyed a poem with such sad subject matter, but I think you handled the subject really well. I found it very evocative of certain canon incidents, but at the same time you made me consider the situation of squibs in more depth than I have done before. You made me think and feel a lot, which I think is really impressive for a fourteen-line poem. Well done!
I like this poem very much. I like the fact that it is in a sonnet form, which imposes a discipline of lines, meter, and rhyme. The words are all used precisely and plainly, so that every phrase is clear and understandable. The subject is refreshingly unhackneyed; occasionally one reads something about the general fate of Squibs, but not very often.
The poem invites one to speculate about what other fates may have been open to Squibs and their families, other than to hide the child like a shameful family secret, or, even worse, do away with the child altogether, and what percentage of families with Squibs actually availed themselves of these other possibilities. Then one starts to speculate about the relative lack of connectedness between the Magical and Muggle worlds, and the failure of families to see their other options. I could go on and on (but I won't) about the various lines of imagination that this poem opens up. Lots of plot bunnies here.