- In the novel Deny Thy Father, Riker's mother is given the name Annie.
Riker's only child, William, was born April 15, 2335 in Valdez, Alaska. Two years later, his wife Betty died. Riker was a civilian strategist for Starfleet and was kept away from Earth by his duties for extended periods, forcing his son Will to largely raise himself. Kyle eventually abandoned his son altogether in 2350 when Will was only fifteen years old. (TNG episode: "The Icarus Factor"; ST - The Lost Era novel: Deny Thy Father)
In 2353, Riker was stationed on Starbase 311 when the Tholians attacked. When the away team from the USS Berlin arrived, they found that Riker was the only survivor. He was then transferred to Starbase 84 for better medical care.
Eventually, he wound up at Starfleet Medical in San Francisco where Doctor Katherine Pulaski oversaw his rehabilitation. Pulaski and Riker became romantically involved in an intense relationship that lasted just over a year. Pulaski later said that she would have married him "in a cold minute", but realized that his priorities were elsewhere. They had remained friends ever since then. (TNG episode: "The Icarus Factor"; ST - The Lost Era novel: Deny Thy Father)
In 2357, at the request of Admiral Owen Paris, Ensign Kathryn Janeway assisted Riker in uncovering the involvement of Vice-Admiral Horace Bonner in the Tholian attack on Starbase 311 four years earlier, as well as several attempts on Riker's life. (VOY novel: Mosaic, ST - The Lost Era novel: Deny Thy Father)
Kyle and his son were reunited in 2365 when Will, now first officer on the USS Enterprise-D, was offered command of the USS Aries. Kyle came aboard the Enterprise to brief Will on the Aries and its current mission. Though Will ultimately turned down command of the Aries, he and Kyle took the opportunity to finally settle their differences and to compete at anbo-jyutsu. (TNG episode: "The Icarus Factor")
By 2371 Kyle Riker was engaged to Brenda Sorenson. Both came aboard the Enterprise so that Riker could consult regarding the Tholians. Riker and his son disagreed on how to proceed with the investigation into the Tholian assaults on Federation and Klingon territory. (TNG comics: "The First Casualty", "A Handful of Dust")
In 2379 Riker was the assigned Federation representative on Delta Sigma IV for its centennial celebrations and the reintegration of five mixed members of the Bader-Dorset population that Starfleet Medical had declared cured of a worldwide lifespan-shortening virus caused by the inhalation of the native Liscom gas.
When one of these subjects, El Bison El, murdered another, Unoo of Huni, Riker tracked him across the planet, attempting to stop massive outbreaks of violence along the way. Riker correctly assumed that the Liscom gas had also drugged the natives into their peaceful coexistence, and that the "cure" in Bison's system triggered people's natural aggressive impulses. (TNG - A Time to... novel: A Time to Love)
Riker was pursued and eventually caught by his son Will, and once they were reunited, Kyle talked him into helping search for Bison and stop the widespread damage. The two ultimately captured Bison, though their Flyer was shot down and they are forced to cross the country on foot. Upon encountering a final violent situation, Kyle Riker pushed his son to the ground and took a disruptor blast meant for him. Kyle Riker died, sacrificing his life to save his son's.