Presumably, Great Grandma Rose was the previous tenant and took in Kylie when her parents divorced. Once Rose passed on, Kylie became the new primary. Her bedroom was adorned with a shrine to Rose. Kylie believed she felt Rose's presence in the apartment from time to time and longed to communicate with her. About a year after Rose's death, Kylie activated the Ghost Beacon in her bedroom and inadvertently attracted Achira straight to her. Achira possessed her and left the apartment to spread her disease.
When Eduardo Rivera inadvertently made a wish, Duophanes granted it. Eduardo found himself in Kylie's bedroom and soon realized he was trapped in Pagan. During the Grundel case, Kylie was woken up late to join the other Ghostbusters investigate an emergency call in the area.