Family
While Spock considers his "family" to be Kirk and McCoy, his parents have just as strong an impact on his life, especially during his formative years. Sybok is the only additional blood relative to surface. Though family relationships are sometimes strained, there is love among them, and wisdom to be gained from one's elders.
Sarek. (Mark Lenard) Spock's father is a Vulcan ambassador of great renowned. While his diplomatic missions always proceed smoothly, his personal life is tremulous. Married three times, his first wife (a Vulcan princess) died after the birth of his first son Sybok, who rejected Vulcan teachings. Five years later he wed the human Amanda Grayson, who bore Spock. Through his son's childhood Sarek was supportive of his decisions, but he didn't agree with Spock's attending Starfleet Academy. This caused an 18-year rift between father and son that ends only as the two are forced to meet for a conference. As the Enterprise transports Sarek and Amanda among the diplomats, Sarek's heart problems are discovered. Only an operation, with blood transfusion from Spock, can save him. Though it takes some maneuvering to tear the first officer away from his duties, he does provide the transfusion and remains on good terms with his parents for many years thereafter.
After Spock's death, Sarek tells Kirk of a means to revive him in The Search for Spock, and speaks in Kirk's defense in The Voyage Home. His concern for Spock and his friends is clear, even if openly expressing fatherly love is not very Vulcan. He shares many traits with his child: his wisdom, open-mindedness towards the Federation, physical strength (and the mastery of ancient Vulcan fighting techniques), and a marked affinity for humans. While Sarek is not given to bursts of anger like Spock, he can be weary and sullen. After his return from the 20th century, Spock drifts again from his father. Sarek's final action is to negotiate the Federation-Legaran treaty in 2366, with Captain Picard's help. He dies with his human wife, Perrin, and Spock eventually comes to know his love through his own mind meld with Picard. Though symbolic of Vulcan patriarchy, Sarek is capable of sensitivity and discretion, bestowed on his son.
Amanda. (Jane Wyatt) Spock's mother has always been able to give him the open affection he needed, denied by his father and other Vulcans. She also encourages him to embrace his human side, and feels somewhat hurt when its rejected. When teased by other children or troubled with some aspect of Vulcan discipline, Spock would cry on Amanda's shoulder, though aiming for non-emotion into his teenage years. Yet she's not just a "wet blanket," but intelligent and perceptive. In Journey to Babel, she sees Spock and Sarek's "Vulcan logic" for what it really is: universal stubbornness. She seems to enjoy analyzing her husband's "feelings," and he appreciates her insights.
In The Voyage Home, Amanda believes it's not only important to teach the reborn Spock encyclopedic knowledge, but emotional awareness. The question " How to you feel?" is posed, and Spock is baffled. Yet at the end of his adventure he's able to say to Sarek, " Tell my mother I feel fine." From then on there is an emotional edge to Spock, who remains generally expressionless but displays that extra bit of anger or compassion for impact. Though Amanda's lessons take much longer to learn (a lifetime or two!), they are just as profound as any Vulcan ritual, and stay with Spock longest.
Sybok. (Laurence Luckinbill) is Spock's half-brother, a pure Vulcan. However, Sybok rejected the path of pure logic and became a religious zealot, on a quest to find the mythical origin-point Ska-Ka-Ri. Jolly, charismatic, and ever willing to use his Vulcan physic abilities to his advantage, he finds followers. He sways many by taking their "pain," relieving a particular moment of guilt, loss, or sadness and freeing the mind of negative emotions. To find his mythical planet he needs a starship, and hijacks the Enterprise. Sybok meets his match with Kirk, however, who "needs his pain" and can't be won over. Nor can Spock and McCoy, who stand by their captain. When finally confronted with "God", Sybok realizes it's actually a malevolent alien, and sacrifices himself to destroy the being. One of Trek's better "misguided" villains, Sybok shows the dangers of a Vulcan run amok, stronger than any human and willing to exercise this power. He tests Spock's loyalty, which of course belongs to Starfleet.