I'm going to make a hash of the issue. You are an illustrator, and you make illustrations for a children's book written by an author. It is a work that you make and that belongs to you, for which you grant a licence to the publisher or the author, or both. In such a case, is there a resale right that applies? If so, in what context does this apply?
On January 31st, 2019. See this statement in context.