More informal and childish:
* Little monster: Implies mischief and naughtiness.
* Snot-nosed kid: Used for a rude and disrespectful child.
* Spoiled brat: Emphasizes entitlement and bad behavior.
* Pests: Describes annoying children.
* Little rugrat: A playful but negative term for a young child.
More neutral:
* Child: A general term without any negative connotation.
* Kid: A more informal version of "child."
* Youngster: A slightly more formal term for a child.
* Offspring: A neutral term for a child, often used in a more formal context.
More formal and negative:
* Troublemaker: Used for someone who causes problems.
* Delinquent: A more serious term for a young person who breaks the law.
* Miscreant: An old-fashioned term for someone who behaves badly.
Other options:
* Imp: A mischievous and mischievous child.
* Little devil: A playful but negative term for a child who is difficult to control.
It's important to remember that these synonyms all carry their own connotations, so choose them carefully based on the context and your intended meaning.
It's also worth considering whether using a negative term like "brat" is truly necessary. If you're trying to describe a child's behavior, there are often more constructive ways to do so.