The Death of Spock (Yesteryear Timeline)

In an alternate timeline, Spock was killed at the age of seven during the Kahs-wan ritual on the 20th day of Tasmeen in the Vulcan year of 8877 (which equated to the Earth year 2237). Spock's death had a profound impact on his parents, Ambassador Sarek and Amanda Grayson, who separated after Spock's death. Not long afterwards, Amanda was killed in a shuttlecraft accident at Lunaport on her way back to her native Earth. Sarek did not remarry after his estranged wife's death. 
Many years later, it was Sarek who discovered Saavik on Hellguard, an abandoned Romulan outpost. He had also met Thelin, the former first officer of the USS Enterprise, and David Marcus at the Andorian Science Institute on Andoria in 2274. He experienced a rare lapse of emotional control on that occasion as David reminded him of his late son. 
Sarek was later killed at Starfleet Headquarters when the Cetacean Probe ravaged Earth's biosphere in 2286.