An application of "They" and "Them"

Firstly, I am not a linguist; I don't even have my GED, though literature has been an indelible sculptor of my person as far back as my memory permits. While working recently on a piece of creative writing, I encountered some issues concerning purely my inability to marriage a love of literary devices in the form of total technical corruption of the english language with proper english grammar. LOL. I am trying— in desperation— not to indulge myself, here. In my ignorance I have come across something that I now eyeball with doubt. I am unable to tell whether these are errors forged in my pursuit of cadence, or acceptable grammatical applications. The passage is as follows, with concerned areas boldened and understruck:

The village’s crude furnaces became pregnant with his nightly projects; their evenings filled with the incessant clangour of smithwork both delicate and relentless, the likes of which their tidy hamlet had not seen since the meagre colonization of the area some thirty years past. He did not sleep— such was an idleness impermissible to him when (while?) by day, grimly, he watched their crippled young laugh and hobble, shriek like jays and warble like meadowlarks, or sweeter still fall into the sleepy mumblings of the parish doves at their bedsides, (—? ;?) a rufous forest variety, quite tame and kept throughout the village in simple wicker structures that evinced a great deal of latent skill in weaving, as well as an innate sense of integrity in structure. Some of the older village folk, alerted to his sleepless work in the kiln pits for the children (and the children of their children) brought him magnificent textiles of a likeness unseen to him as was his selfless stamina to they. (them?)