|Manner of Death:||Mysterious respiratory illness|
|Occupation:|| High school teacher|
|Marital status:||In a relationship with Greg|
|Significant Other/s:||Greg (boyfriend)|
|Family:|| Leda clones (sisters/genetic identicals)|
|Portrayed by:||Tatiana Maslany|
|Only appearance:||"Mingling Its Own Nature With It"|
Her appearance in "Mingling Its Own Nature With It" is seen only through a series of video diaries, possibly suggested by the Dyad Institute, chronicling her declining health from the first day of the diagnosis that unidentified polyps were discovered on her lungs to possibly her last day in a hospital. According to Delphine Cormier, Jennifer was the first clone to show symptoms, six months before Katja. Three days after Jennifer died, Delphine provided these videos to Cosima, who patiently listened to her fellow clone's introspection, heightening Cosima's awareness of her mortality and thus her mental strain.
In the videos, Jennifer revealed that she was contacted, offered treatment, and flown to the Dyad Institute as courtesy of Dr. Leekie, with the accompaniment of her boyfriend and monitor, Greg. At the Institute, Jennifer was supposedly given a new treatment each week, but no avail. Her health drastically kept deteriorating to the point that she could not digest food properly, was coughing up pus and could not even breathe. Cosima criticized Jennifer's 'fake hope' and harshly attributed that fact to her monitor as he kept her "completely in the dark", making Jennifer naïve of her own illness, her existence as a clone and of her monitor. However, Delphine claimed that Jennifer's naïvety did not compromise her treatments. Near the end of her supposed last diary entry, Jennifer boldly stated that Dr. Leekie has outright lied to her and that she will eventually die.
Jennifer's body was later autopsied by both Delphine and Cosima in hope of finding the source and possible cure of the illness that plagued her, Katja and its newest victim, Cosima. Eventually it was discovered that the illness was auto-immune as more mature and pronounced growths were found on Jennifer's uterine wall, indicating that the illness originated there and spread throughout Jennifer's body. This led Cosima to conclude that the illness was a plausible cause for Jennifer's infertility.