Page "Yesteryear (Star Trek: The Animated Series)" Paragraph 3

In the new timeline, history has recorded that Spock died at age 7 undergoing the Kahs-wan ordeal on Vulcan.

However, Spock remembers that when he took the Kahs-wan, his life was saved by Selek-an adult relative-when a desert creature had attacked them.

Realizing what must have happened, Spock knows he must go back through the time gate to his Vulcan childhood, and save the life of the child he was.

At first, this proceeds smoothly: Spock assumes the identity of Selek, and is welcomed into the home of Sarek and Amanda Grayson.

" Selek " journeys into the desert to find his younger self, and saves the boy.

However, I Chaya-Spock's pet sehlat-has been gravely wounded.

Young Spock is offered a choice: either I Chaya can be treated with medicines ( but will live in obvious pain ) or his pet can be allowed to die with dignity.

Young Spock chooses the latter, and I Chaya dies peacefully.

By making this choice, Spock has thus chosen the Vulcan way of life-logic and emotional control-and his elder self, successful in repairing history, returns to the restored present day.