Keiko O'Brien

In 2367 Keiko Ishikawa, a human female of Japanese ancestry is working onboard the USS Enterprise NCC-1701-D. Not as a member of the Starfleet crew but as one of the many civilian personnel also onboard the ship. Her job is as a botanist.

Her hobbies also include growing bonsai trees in her quarters. She plays the clarinet and is a member of a musical group lead by Data, which often performs in Ten-forward.

Its her friend Data who introduces Keiko to Miles O'Brien. A Starfleet Transporter Chief. They eventually fall in love and marry in Ten-forward in 2367.
In 2368 the O'Briens first child, a daughter is born. They call her Molly. Her birth doesn't come without problems thought.
Due to the Enterprise being damaged by colliding with a quantum filament most of the ships power had been lost. Keiko along with several other crew was trapped in Ten-forward.
Heavily pregnant Keiko goes into labour. With no medical staff in Ten-forward and unable to contact sickbay because of the ship-wide power-loss , Worf had to deliver the Baby.

In 2369 Keiko is one of four crew who are reduced to the physical size of children after travelling through an energy field in a shuttle. But thanks to Dr Crusher and the transporter Keiko, Picard, Giunnan and Ro are returned to their normal size.

Later in 2369 the O'Brien family leave the Enterprise after Miles takes up a posting on the new Starfleet outpost of Deep Space Nine on a Bajoran space station.

DS9 is orbiting the planet Bajor which has recently been freed from occupation. With no call for a botanist on DS9 Keiko opens a school.

In 2371 with most families leaving or left the station dues to the Federation / Dominion War, Keiko has to close the school.

Knowing she's no longer happy Miles suggests she join an agrobiology expedition to Bajor that will last for six months.

They see each other as often as possible with Bajor being only a shuttle ride away.

In 2372 Keiko becomes pregnant again. However early in the pregnancy Keiko is injured in a runabout accident and Dr Bashir is forced to transfer the baby into Kira's body in order to save it. But this is a one way process and Kira must carry the baby to term.
When the baby is born in 2373 the O'Briens call him "Kirayoshi O'Brien"

After the Federation / Dominion War ends the O'Brien family leave DS9 when Miles takes a job at Starfleet Academy. After so many years in Space the family are going home.