Shu Ya 叔牙 and the house of Shusun 叔孫

Shu Ya 叔牙 "Uncle Ya" (died 662 BCE), also called "Ducal Son" Gongsun Ya 公子牙, or "Uncle" Xi Shu Ya 僖叔牙, was a son of Duke Huan of Lu 魯桓公 (r. 712-694) and the ancestor of the lateral house Shusun 叔孫. He served his brother Duke Zhuang 魯莊公 (r. 694-662) as a consultant minister during the Spring and Autumn period 春秋 (770-5th cent. BCE) in the state of Lu 魯.

When Duke Zhuang fell ill, he consulted Shu Ya about a possible successor, and Shu Ya recommended their common brother Qing Fu 慶父, while another brother, Ji You 季友, preferred Prince Ban 般 (also written Ban 班), a son of Duke Zhuang by a secondary wife. Enraged about Shu Ya's unusual suggestion, Duke Zhuang ordered Ji You to kill their brother.

Shu Ya's son was, nevertheless, named head of the family that was given the name of Shusun 叔孫, literally "grandsons of Uncle (Ya)". The Shusun family became one of the mighty Three Huan families 三桓 that challenged the ducal house of Lu.