For all my longer works (i.e. the novels) I write chapter outlines so I can have the pleasure of departing from them later on.
Writing for children, you do bear a responsibility to not include overt or graphic adult content that they are not ready for and don't need, or to address adult concepts or themes from an oblique angle or a child's limited viewpoint, with appropriate context, without being graphic or distressing.
I can understand the natural anxiety of readers when waiting for another installment of a favourite series, but I think it is much more important to get a book right than it is to have it appear on time.
I love you too, but my time with you has passed.
When the dead do walk seek water's run, for this the Dead will always shun. Swift river's best or broadest lake to ward the dead and have and make. If water fails thee, fire's thy friend, if neither guards it will be thy end.
Death and what came after death was no great mystery to Sabriel. She just wished it was.