Parricide was the act of murdering one's own father (patricide), mother (matricide), sibling (fratricide) or a close relative. In the galactic community, parricide was regarded as a particularly outrageous crime. Even the nobles of the Tapani sector, who saw murder as a viable method of dealing with intractable issues, considered parricide a very serious offense to their social order. However, several cases of parricide had a major impact on galactic history. Most notably, the Galactic Emperor Palpatine himself had become his family's patriarch at age seventeen, before even reaching the age of responsibility, upon murdering his father, mother, and siblings. Decades later, the heads of the Great Houses of Serenno were all replaced after a mass parricide known as the Cleansing of Serenno.