What crime did Kenny say grim and gram committed in Freak the Mighty?

In "Freak the Mighty," Kenny, also known as "Kenny Kane," accuses Grim and Gram of committing the crime of kidnapping when they take Max away from his father. Kenny believes that since he is Max's biological father, he has the right to raise Max himself. This accusation reflects Kenny's violent and manipulative nature, as he tries to exert control over Max and intimidate Grim and Gram.