This is a book I remember loving when I was young, but I can’t remember the name of the book or the author. (I read it probably in the early 90's.) I remember it being about a girl and a young boy (who might have been her brother) living on a space station and somehow getting stranded on the dark side of a moon or planet. There were some alien animal things that everyone was terrified of that lived on the dark side, but I seem to remember the kids befriending some of them. Edited to add more stuff I think I remembered: I remember the alien animal things lived in a pack, and had piebald/mottled skin. They were considered to be dangerous and terrifying, but turned out to (I think) be telepathic or otherwise able to communicate. I don't remember how it ended, but I'm pretty sure there was more than one book.
Could it be Larklight by Philip Reeve?
When I read your description, I was reminded of this story which I only have a vague memory of myself. I remember the story detailed the Lunar flora and fauna, and the two children, girl and boy, are the main characters, although the story continues on past this scene—to where, I am not sure.
From the Wikipedia page,
The story begins at Larklight, a house that orbits Earth's moon, where the Mumbys receive a visitor from the Royal Xenological Society, a Mr. Webster, who is revealed to be an extraterrestrial resembling an enormous white spider. Art and his sister Myrtle escape; but their father is captured and held prisoner.
Art and Myrtle leave in an escape pod and crash-land on the Moon, where they are encased with predatory larvae of the Potter Moth and freed by pirate Jack Havock and his crew.