In the episode “Hassle in the Castle”, Timmy enters the fairy fishbowl because he was denied entry and he believes they were hiding something from him.

Within their home, he discovers the Hall of Infamy, a hall lined with with portraits of past godkids who had their godparents taken away from them. After stealing a wand and entering the hall (believing it was actually the hall of fame), he brings to life three of the paintings of the children, who each speak of their misdeeds that got Cosmo and Wanda removed as their fairy godparents.

Near the end of the episode, Wanda reveals that one of the children, Mary Ann, the primary antagonist of the episode, abused their magic to orchestrate the death of Arch Duke Ferdinand, setting off the chain reaction of World War 1.

As we all know, Germany was left embittered and in an disastrous economic state after WW1 ended due to the Treaty of Versailles was abysmal. The Nazi party’s rise to power was a result of this, as Hitler promised to restore stability, law, and order to the country. The rest, as they say, is history.

Thus Cosmo and Wanda, canonically within Fairly Odd Parents, are indirectly responsible for millions upon millions of deaths, including atrocities such as The Holocaust, and should be labelled as war criminals.

I will be taking no further questions at this time.