Son of Slappy is the second book in the Most Wanted book series.
Jackson Stander is a good kid. His parents and teachers all trust him and know that he would never do anything wrong. But after visiting his grandfather's house and meeting Slappy, Jackson is compelled to do evil things. Slappy has almost all control over Jackson, he even starts referring to him as his son because of all the mischief being caused. Jackson must figure out a way to defeat Slappy. However, when he discovers that his sister Rachel appears to be Slappy's daughter, the question of if he will be Slappy's son starts to arise. So the question is, will Jackson really turn-out to be Slappy's son or not?!
- Some of the story was very similar to Horrors of the Black Ring. Jackson Stander is a kind kid who was controlled by an evil villain to do bad things while his sister, Rachel teased him for being a goody-goody. Beth Welch was also a kind kid who was controlled to do evil things while her schoolmate, Anthony Gonzales teased her for being a goody-goody.
- This is one of the few books in which Slappy succeeds.