Sarah was born on the planet Huntress as a member of the Clan's eugenics program. She successfully tested out of her sibko as a MechWarrior and quickly moved up within the ranks of her Clan. Due to her innate skill, she was able to earn the Weaver Bloodname and in 3046 was elected as saKhan of Clan Smoke Jaguar.
When Leo Showers, her mentor, became ilKhan in preparation of Operation Revival, Sarah competed with Lincoln Osis for the position of Khan. Though she was unsuccessful, Sarah still retained her title of saKhan and was politically connected within her Clan.
Prior to the main invasion of the Inner Sphere, Sarah would lead her Clan's operations in the Periphery as head of the elite Shroud Keshik of Alpha Galaxy. During this sweep, Sarah led the entire 362nd Assault Cluster against Santander's World and end the rule of the bandit king Helmar Valasek. Her actions during these initial engagements increased her standing within her Clan.
However, Sarah would find her political position diminished by forces beyond her control. Her protégé, Star Colonel Cordera Perez, was in command of the Smoke Jaguar forces on the world of Turtle Bay and ordered the razing of the city Edo when the uprising there could not be crushed. The dezgra use of orbital bombardment against civilian targets by a subordinate cast a shadow upon Sarah. Worse, when Sarah realized that more troops would be needed to secure her Clan's conquests, she lost more face in the eyes of her contemporaries for failing to crush the resistance.
Upon the death of ilKhan Leo Showers, Kincaid Furey, a political rival, placed the blame for the Smoke Jaguars' recent setbacks at Sarah's feet. In her weakened political position, Sarah would narrowly lose an impromptu election and Kincaid would become the new saKhan of Clan Smoke Jaguar. While the Clans returned to their homeworlds to elect a new ilKhan, Sarah would be challenged by many warriors to a Trial of Grievance for her perceived failures. After defeating eleven individual opponents, her victories regained her much lost honor and prestige amongst her peers to place her in a position to take back her standing within the Clan. When Kincaid attempted to outmaneuver the new ilKhan Ulric Kerensky and failed, Sarah challenged and defeated Kincaid. Sarah once again was saKhan. However, the challenge would leave her wounded and she missed her Clan's assault on Luthien. However, she was fully healed in time for the Battle of Tukayyid.
Sarah Weaver led Beta Galaxy during the fighting on Tukayyid. Her galaxy's target was the city of Port Racice. In an aggressive move to regain their Clan's lost honor after their defeat on Luthien, Beta Galaxy would perform a combat drop into the marshes of the Racice River Delta. The Com Guards 5th Army would avoid direct combat and use the terrain to their advantage to stage ambushes and hit-and-run attacks. This angered the Clan warriors while also negating their technological advantages. In pursuit of her attackers, Sarah Weaver led Beta Galaxy deeper into the marshes in an attempt to destroy her opponents. Once there, elements of the 207th Division surrounded Beta Galaxy's Command Star where Sarah Weaver was killed during the third day of fighting.     
While her preferred choice of BattleMech is unknown, Weaver's last 'Mech was a Warhawk. Weaver was killed at its controls after a Com Guard artillery strike struck its rear torso and sent its fusion engine critical. 
- Era Report: 3052, p. 90, "Sarah Weaver profile"
- Tukayyid, p. 29 "Campaign: Clan Smoke Jaguar"
- Tukayyid, pp. 32-33 "Battle in the Delta "
- Invading Clans, p. 62 "Tukayyid: The Crucible"
- Wolf Clan, p. 7 "Days of Armageddon - Smoke Jaguar"
- ComStar, p. 70 "Battle of Tukayyid"