The Kirk family ancestry included settlers who pioneered the American frontier in the 19th century, and the Kirks of the early 23rd century rediscovered the impulse for untamed spaces. After his early childhood on Earth, James T. Kirk the son of George Samuel Kirk, Sr. and Winona Kirk was living on Tarsus IV by the age of 13, his brother's family later lived on colonies as well. (TOS episodes: "Spectre of the Gun", "The Conscience of the King" and "Operation -- Annihilate!")
George and Winona's other son George Samuel Kirk, Jr. (called "Sam" only by his brother) was a researcher, hoping to transfer to the Earth Colony 2 research station in 2265. Sam, along with his wife Aurelan and three sons, joined his younger brother for a farewell visit before the USS Enterprise departed for her five-year mission. It was the last time Jim saw Sam alive. Sam ended up on Deneva, with his wife and son Peter by 2267. The neural parasites invaded Deneva that year and killed the couple, but Peter survived the attack. (TOS novel: Enterprise: The First Adventure; episodes: "What Are Little Girls Made Of?" and "Operation -- Annihilate!")
Jim Kirk recognized the impact his life in Starfleet had on his family life. In 2287, while camping with his friends in Yosemite National Park, he referred to himself, Spock, and McCoy, as the only family that men like themselves were likely to have. (TOS movie: Star Trek V: The Final Frontier)
Members of the Kirk family
- Samuel Abraham Kirk, father of Tiberius
- Valeria Messalina Willams-Kirk, wife of Samuel Abraham Kirk
- Tiberius Kirk, father of James and George Samuel Sr.
- James Kirk, son of Tiberius
- George Samuel Kirk, Sr., father of George Samuel Jr. and James T.
- Winona Kirk, wife of George Samuel Sr.
- George Samuel Kirk, Jr., eldest son of George Samuel Sr. and Winona
- Aurelan Kirk, wife of George Samuel Jr., together they had:
- Alexander Kirk
- Julius Kirk
- Peter Kirk
- Craig Kirk
- Sinjin Kirk, son of Craig
- a daughter (possibly Jamie Samantha Kirk)
- Aurelan Kirk, wife of George Samuel Jr., together they had:
- James T. Kirk, youngest son of George Samuel Sr. and Winona
- David Marcus, son with Carol Marcus
- unnamed boy, with Miramanee
- Joseph Kirk, with Teilani
- George Samuel Kirk, Jr., eldest son of George Samuel Sr. and Winona
- Winona Kirk, wife of George Samuel Sr.
- Tiberius Kirk, father of James and George Samuel Sr.
- Valeria Messalina Willams-Kirk, wife of Samuel Abraham Kirk