Hi Becky,
Thanks to you daughter for posting the photos. I'm not sure about the small one, but the larger one looks like it is in the Formosae section of dendrobiums. These do need to have both water and fertilizer decreased during the cooler months, as Jeff pointed out. When new growth starts in the spring, you can adjust to more water and feedings then.
They both look healthy, even the single leaf does in my opinion.
Good luck with them...and keep us posted on their progress.
David