Lefler's parents were plasma specialists that were in short supply in a certain sector. This meant they were traveling from base to base during her childhood. Lefler therefore could neither call a place 'home' nor develop friendships, jokingly claiming her first friend had been a tricorder. She graduated from Starfleet Academy in the 2360s and, in 2368, was posted on the USS Enterprise-D. (TNG: "The Game")
Lefler served as mission specialist for a mission exploring the Phoenix Cluster. During this time, she had a brief romance with Wesley Crusher while he was on vacation from Starfleet Academy. She and Wesley discovered a plot by a rogue group of Ktarians to take over the Enterprise (and subsequently, Starfleet), using an addictive game to get control over the crew. She helped to analyze the game's effects and in examining Data when he was deactivated. She eventually succumbed to the game, but Wesley had enough to go on to foil the plot and free everyone from the game's control, including Lefler. Several days later, before Wesley was taken back to Starfleet Academy, Lefler helped him pack and they exchanged their goodbyes, during which she gave Wesley a copy of her laws as a gift. (TNG: "The Game")
Robin Lefler was played by Ashley Judd.
Originally, Lefler did not appear in "Darmok". This is evidenced by the call sheet for 18 July 1991, which listed an "uncast actress" in the role of Lieutenant Larson, which could also be an earlier name for Lefler which was then changed.
In April 2002, ZENtertainment (a now-defunct Hollywood news source) reported, "Ashley Judd was on Letterman the other night to promote her new movie, High Crimes. Dave surprised her with a clip of her appearance on TNG, where she went on a date with Wesley Crusher (Wil Wheaton). Judd mentioned that she was reprising the role (of Robin Lefler) in Star Trek Nemesis as Wesley's wife."   This was also reported by About Sci-Fi, which added to the report, "Wil Wheaton, however, says he's heard nothing about that. Somehow, I'm not surprised Wesley doesn't know he's married." Later on, "Judd's spokesperson denied this cameo appearance."  In August 2002, Wil Wheaton found out and reported that his scene had been cut from Star Trek Nemesis. There was no mention (by him) about Judd or Lefler.
According to the video game Star Trek: Starship Creator, Lefler was born in Trenton, New Jersey to parents Morgan and Mark Lefler. However, the short story Lefler's Logs states that her father's name is Charles.
In Peter David's New Frontier series, Lefler was the chief operations officer of the USS Excalibur, under the command of Captain Mackenzie Calhoun (M'k'n'z'y of Calhoun). Her mother was an immortal, who went by the name "Morgan Primus" and seemed to have been nearly every character portrayed by Majel Barrett-Roddenberry.