In an alternate timeline in which the UK-201 never crashed on Dido, Jeran Dalton was a surgeon on Astra. In some versions of the timeline, he became the husband of Vicki Pallister.
Biography
First timeline
Jeran was present on the scene of a disaster on Astra when a meteor shower struck the observatory. Jeran examined the body of Newton Pallister and found him dead. He comforted Vicki as she grieved the death of her father. The the following years, Jeran and Vicki got to know more about each other and eventually got married. They gave birth to two girls, Carla and Maria.
Carla died in a rebel attack while performing humanitarian work in Astra's Outer Provinces. Jeran and Vicki received the news of her death.
Jeran died after attending a conference intended to deal with the spread of space plague, during which he caught the plague himself. Maria, as governor, visited his grave around the time she negotiated peace with the rebel forces.
Second timeline
When Vicki discovered she could alter pivotal moments in her life, she travelled back in time to convince Jeran not to attend the conference. Jeran survived and spent his later years with Vicki. During one conversation, he reflected how he and Vicki did not talk about Carla following her death, and suggested they should remedy that. This influenced Vicki to travel back and save Carla's life too.
Third timeline
Vicki prevented Carla from travelling to the Outer Provinces, but the rebels gained the upper hand and Maria never became governor. The new governor failed to negotiate with the rebels, making Jeran and his family into refugees. Jeran remarked that the governor would soon be forced to surrender.
Fourth timeline
After Vicki warned her father about the meteor shower and saved his life, Jeran arrived at the observatory to aid the other casualties. He did not properly meet Vicki she never became his wife.
Fifth timeline
Vicki tried to recreate the circumstances in which she met Jeran and return to her family life. She met Jeran again at the observatory when her father died and eventually they married. However, subtle changes to the course of events as well as pure chance meant the couple gave birth to a son named Carl instead of Carla, as well as a different version of Maria.
Jeran was disturbed by Vicki's insistence that Carl and Maria were not their proper children. Unable to see her old family again, Vicki chose to return to the UK-201 and let the true course of events play out.
Prime timeline
After Vicki escaped the alternate timeline and returned to travelling with the First Doctor, her life with Jeran never happened. Vicki, however, could still remember her experiences and chose to preserve the memory of her family. (AUDIO: The Crash of the UK-201)