[1][2] Chuqui Huipa was the daughter of the Inca Huayna Capac and Rahua Ocllo, and thus the full sister of Huáscar.
Her reason is reported to have been personal discontent with Huáscar, and disapproval of his execution of her late husband's executors.
Huáscar viewed his brother Atahualpa as a threat and had many people at court executed because he believed their loyalty to be faltering.
Her new conditions also caused a depression, and she reportedly took to abuse coca, both to sleep at night but also during day time.
Upon entering the city, the loyalists of Atahualpa reportedly called Rahua Ocllo a concubine rather than a queen in order to present Huáscar as illegitimate.
She explained that though he was her son, he deserved his present predicament because of his execution of Atahualpa's ambassadors, for all his misdeeds, and for having dragged down his entire family including her in his ruin without cause, and slapped him in public.