The Beagle Brats are the nephews of the DuckburgBeagle Boys. Seemingly their moral compass is not well-defined at their current age, as they sometimes can be as criminal as their uncles, sometimes are just bratty, and sometimes they do downright legal work like shoe-shining, much to their uncles' chagrin.
Numerous similar young relations of the Beagle Boys appeared in the DuckTales episode "Take Me Out of the Ballgame". They were also referred to as the Beagle Brats, although it is not specified how they are related to the rest of the Beagle Boys.
Ma Beagle and the Beagle Brats in Take Me Out of the Ballgame.
Ma Beagle lecturing one of the Beagle Brats.
Baggy, Bigtime, and Burger as spectators with some of their younger relations.