Yesterday's SonA. C. CrispinStar Trek: The Original Series, book 11

Characters in Yesterday's Son

3 characters, main characters first.

Main characters

Mr. Spock
Also in Web of the Romulans, Probe, The Vulcan Academy Murders, Star Trek - Ishmael, Star Trek - Time for Yesterday, Prime Directive, Collision Course, Sarek, Star Trek Adventures - Spock, Messiah!, Star Trek Adventures - The Price of The Phoenix