In mythology, Eris caused a quarrel among goddesses that sparked the Trojan War. In real life, Eris also caused strife, forcing scientists to produce a strict definition of the term planet - and that eventually led to Pluto losing the status it had held since its discovery in 1930.
According to the website, Skyscript, Pluto also has discord behind the meaning of its name:
In Greek mythology Pluto is Hades, god of the underworld, and the era of Pluto, including both Nazism and the use of nuclear bombs, certainly presents an unparalleled vision of hell. At its worst, Pluto symbolizes the abuse of power, hellish experiences, and the threat of death, either physically or to a sense of self. In mythology we learn that Hades donned the helmet of invisibility when leaving the underworld. Thus Pluto also speaks of that which is invisible or absent.
All, it seems, is not happy in the sky, but luckily they've both been officially categorised only as 'dwarf planets'. So that's all right then.