Yeah, I know now that you guys are right.

At least this hasn't been all for naught. After posting, I read and learned a lot about foxes that I didn't know (even if some of it was depressing), and I can practice building shelters with the materials in my backyard for the fun of it and for the sake of learning.

As for my friend the fox, if he really starts to suffer I'll see that he is humanely taken care of.