Read this order
Child → Book: A beginner learning something new, a child's education or a new project whose details are not yet known.
What changes in reverse?
Book → Child: New knowledge, early study or information about a child. The emphasis is on something still being learned.
Book → Child ↗A practical example
A beginner opening a course book fits Child + Book. An unfamiliar concept introduced in a first lesson fits Book + Child. A literal child is possible, but not necessary when the question concerns a new skill.
Check it against your question
Keep the actual order and ask which part of the example fits your situation. An example illustrates a possible reading; it does not establish facts or promise an outcome.
The meanings behind the pair
Child: Child can represent an actual child, a new beginning or something small and inexperienced. The question determines whether the meaning is literal or describes an early stage.
Book: Book represents knowledge, study, privacy and secrets or information not yet disclosed. It may be a literal book, education or a matter that is still unknown.
These examples show possible ways to read the pair. Your question and the other cards may change the meaning.