During the Cardassian occupation of Bajor, Peri’s grandmother, Jerya, was a Bajoran, who caught the eye of a Cardassian, Gul Shinal Rirset. Jerya eventually escaped with her daughter in 2352 and found herself a refugee. For several years, Jerya went from place to place until she finally settled in a small colony on Hasoor VII. There she met Grishom Katsim and his son Sylar. He and Peri’s mother, Wirhla grew up together and eventually married in 2371 after Sylar graduated from Starfleet academy. Peri was born four years later.
Growing up, Peri found herself between two worlds. A child of mixed species, she never quite fit in with any of those from her heritage - for the most part. Her parents have exposed her to the culture of Bajor and, to an extremely limited degree, that of Cardassia, though often in a negative light. It is enough, however, to spark her curiosity, and make her uncertain of her own place in this world.
Several trips were made to Bajor, but neither she nor her parents were well received, so they remained short save for a year long stint when her father was stationed on the planet per orders of Starfleet - her final year of schooling before she entered the academy. Most of the time, the holodeck was utilised as a tool to teach her about Bajor - and even some about Cardassia, though not to the same extent. It was not uncommon to find her there for other pursuits, particularly finding programmes that allowed her to feel like she was outside, to get her energy out not only by running, but climbing and exploring.
Peri’s love of learning was instilled early in her by her father, a scientist himself. Since Sylar was an officer in Starfleet, Peri and her mother went where he was stationed, which allowed her the exposure to all sorts of opportunities. It was the stars themselves that most interested Peri, what they were made of, how they functioned, and the theories inspired her to ponder what the answers might be.
In 2392, at the age of 18, Peri entered Starfleet Academy, along with her closest friend Ayna, where she majored in Astrophysics with a minor in interstellar anomalies. In 2395, a tragic training accident took the lives of several cadets, including Ayna, marking a dark year in her training. In She graduated in 2396, served on her cadet cruise, and was assigned to her first ship, The USS Thor, in 2397.