Examples of authors “answering” other works through fiction

I'm looking for pieces of fiction where other creatives responded with their own works or adaptions.

A famous example would be Robert Heinlein's "Starship Troopers":
"Ender's Game" is widely thought to be a response to it. So are "The Forever War" and "Old Man's War". The movie adaption also discusses the topics of the book by satirizing some of its themes.

Another example is "The Ones who walk away from Omelas" by Ursula K. LeGuin. This website collects stories about Omelas by authors who responded to the scenario with their own stories, developing new themes, expanding or contradicting the original story.

While writing this post I remembered "The problem of Susan" by Neil Gaiman, which is a response to Susan's treatment in C.S. Lewis' "The last Battle".

Do you know any other discussions in the form of novels and short stories?