Kathleen's early history and childhood is unknown. What is known is that at a young age, she was accepted into the ISF, the feared secret police force. She likely attended the Internal Security College on New Samarkand, where her training included seduction, self-defense and security training.  During this period, she met fellow ISF agent Ninyu Kerai, although the exact nature of their relationship is unknown.
In early 3018,  she was chosen by ISF Director Subhash Indrahar to begin a relationship with Theodore Kurita, son and heir to Coordinator Takashi Kurita, while Theodore was a cadet at the Wisdom of the Dragon academy on Kagoshima. 
Indrahar had a number of reasons for doing so, including using Kathleen to set up a "test" for Theodore to join his Sons of the Dragon organization.  Another was to become impregnated with Theodore's child, to ensure that there would an (albeit illegitimate) heir to House Kurita.
After the revelation that she was an ISF agent, Palmer apparently never had contact with Theodore Kurita again. He was therefore unaware that she gave birth to his child, Franklin.
In 3033, Theodore Kurita, now Gunji-no-Kanrei of the Draconis Combine Mustered Soldiery, revealed to his father and the rest of the Inner Sphere that he had taken Tomoe Sakade as his wife, and that she had bared him three legitimate children.  At this point, the existence of Kathleen's child, Franklin, had become a liability. Knowing her son was in danger, Palmer contacted Warlord Marcus Kurita, who arranged for her son's evacuation and safety with the plan that he would someday use the child as a pawn. The Warlord also arranged for a decoy child to be left in Kathleen's care.
Palmer herself remained on Wolcott when Ninyu Kerai appeared in her apartment. Kerai killed Palmer and the child, destroying all the evidence in a fire. Her last thoughts were of her son, Franklin, being brought to safety. 
Years later, Franklin Sakamoto and his father would finally meet, with Theodore publically recognizing his son. Franklin formally renounced his claim to the throne, and became an officer in the Otomo. 
In 3137, more than a hundred years after her death, Kathleen's great-great-granddaughter through Franklin, Yori Kurita, ascended to the throne of the Draconis Combine, upon the assassination of Coordinator Vincent Kurita. Coordinator Vincent's entire family were either killed or missing at the time, leaving Yori as the only heir despite her "illegitimate" status. 
- 1st Somerset Strikers (sourcebook) p. 54
- Heir to the Dragon (novel) p. 20
- Heir to the Dragon (novel) p. 27
- Heir to the Dragon (novel) pp. 19-28
- Heir to the Dragon (novel) pp. 265-273
- Heir to the Dragon (novel) pp. 277, 290
- Heir to the Dragon (novel) pp. 274-277
- Black Dragon (novel), p.??
- Dragon Rising (novel), p. 296