A day with Bowser Jr. Wiki

Koopapedia is the free Internet encyclopedia site in the Koopa Kingdom that's a parody of Planet Earth's Wikipedia. It first appeared in Two Koopas for a throne part 2 when Bowser Jr., Lemmy, and Iggy were looking up Koopa Castle. That is where they found the section Morton Koopa's death. They didn't find out the information about what happenned on the day of Morton Koopa's death (probably because King Bowser ordered a censorship on Koopapedia to prevent his children from finding out about the truth). But that is where they found a picture of the statue of Morton Koopa Sr where it said "Those who have never witnessed the mighty statue will never know of the great Koopa's true tale".