To determine whether two books are related, we need to consider several factors. First, examine the authors to see if they have a history of collaboration or if one book is a sequel, prequel, or part of a series based on the other’s work. Next, check the themes, subjects, and genres of the books—do they explore similar topics, or are they in the same category? It is also worth reviewing the settings and characters to see if there are overlaps between the two. Furthermore, consider any references or mentions within the text that might indicate one book is inspired by or directly referencing the other.
Additionally, reviews, forewords, or introductions may provide context about whether the author or publishers intended a connection. Lastly, researching any commentary from the authors or literary critics could reveal less obvious connections. Ultimately, the relationship between two books can vary widely and might be explicit or more subtle requiring deeper investigation.