She had not been long in Patiala when she had to return to Fatehgarh at the head of a large Patiala army to rescue her husband who had been captured by Fateh Singh, a rival chief. Back in Patiala she faced a large Maratha force marching towards the town in 1794 under the command of Anta Rao and Lachhman Rao. Raja Bhag Singh of find, Jodh Singh of Kalsia and Bhanga Singh of Thanesar joined hands with her while Tara Singh Ghaiba sent a detachment of troops. The joint force, numbering about 7,000 men, met the enemy at Mardanpur near Ambala where a fierce engagement took place. The Sikhs were severely outnumbered and would have retreated had not Sahib Kaur, alighting from her rath, i.e. chariot, made a brave call with a drawn sword in hand for them to stay firm in their ranks. The next morning they made a sudden charge on the Marathas who, taken by surprise, retired towards Karnal in utter confusion. Bedi Sahib Singh of Una charged the Pathan chief of Malerkotla with cow-killing and attacked him. He was saved by the timely succour given him by Sahib Kaur. In 1796, in response to the request of the Raja of Nahan who had sought help from Raja Sahib Singh of Patiala to quell a revolt in his state, Sahib Kaur proceeded to the hills with a strong force and soon reduced the insurgents to submission. The Raja was reinstalled on the gaddi (throne) and, at the time of Sahib Kaur's departure, he presented her with many rich and valuable gifts in token of his gratitude.

In the summer of 1799, George Thomas, an English adventurer, who had become very powerful and who ruled the country in the neighbourhood of Hansi and Hissar, turned his attention to the Sikh territories on his northern frontier and marched upon Jind. Sahib Kaur led out a strong contingent to relieve the besieged town and, assisted by the troops of other Sikh chiefs, she forced George Thomas to withdraw.

Owing to differences with her brother, Bibi Sahib Kaur had to leave Patiala to take up residence in Bherian, near Sunam, which fell within her jagir and where she had built a fort changing the name of the village to Ubheval. She died there in 1801 in the prime of her life.