Why is my kitten so aggressive?

I guess I would question: are they aggressive, or are they having normal behavior? Yes, some kittens are aggressive because they're scared. They're fearful. That's that fight or flight behavior, and so they may feel threatened. And that could be one reason they could be aggressive. They may be aggressive because that's their normal play and behavior. Biting and chewing can look like aggression or biting and scratching, but it's normal play that has not been directed in the right ways.

Aggressive cats are often just more playful and prey-driven, using you or your furniture to redirect their behavior. Many aggressive behaviors just need to be redirected, so talking to your veterinarian about the specific issues can help with early intervention and redirection of problem behaviors.

Aggression in kittens is usually just play and predator behavior, which manifests as biting and scratching, although they’re not trying to be mean or spiteful. Cats’ behavior revolves around hunting, eating, and sleeping, so if they’re being aggressive, it just means they need to satisfy their need to hunt. To help them release aggression, provide appropriate toys and activities.