Fletcher (born 2348) was found wandering around Dr. Beverly Crusher's
Sickbay after his parents were arrested as Maquis (2363). After a tour
and a long discussion over a meal, Nathan discovered that he wanted
to be a physician and that the fastest route was to join Starfleet Medical.
Dr. Crusher talked with Nathan's family and said she would sponsor the
young man's dream. A few weeks later and after some basic testing and
training he was accepted and sent on ahead.
After graduation (2374) Fletcher worked one year at Starfleet Medical
where he interned as a surgeon, then he was assigned to the Europa Station
(2375) where he was part of the team that treated the Marine Training
Division and the Federation shipyards (Utopia Planitia). After five
years, he transferred to USS Valdemar (2380). He visits Dr. Crusher
on leave. When the Valdemar was recalled for refit, Dr. Fletcher opted
to apply for transfer to SB901 (2385).
Joined Starfleet instead of the Maquis wanting to see and help more
then just his homeworld.