Son of Amir Singh Sandhanvalia, enjoyed at the court of Ranjit Singh the title of "Ujjal Didar, Nirmal Buddh, Sardar i-baWagar (Resplendent presence, pure of intellect, the Sardar with prestige marked) Sardar Lahina Singh Sandhanvalia Bahadur." Like other collaterals of the Maharaja, Lahina Singh was rich both in wealth and intrigue; he first became a partisan of the Dogra faction at the court, but changed sides when Kanvar Nau Nihal Singh came to power. When Kanvar Nau Nihal Singh fell out with Col Wade, the British political agent at Ludhiana, Lahina Singh was deputed along with Faqir Aziz ud-Din to go to Shimla in September 1839 to call on Lord Auckland and demand Wade's removal from Ludhiana. During the struggle for power between Rani Chand Kaur and Prince Sher Singh, Lahina Singh; along with Atar Singh and Ajit Singh, supported the former.

The Sandhanvalias continued their intrigues against their sovereign despite the Tatter's offers of conciliation. In March 1841, the Darbar intercepted a letter from Atar Singh Sandhanvalia, then in British territory, to Lahina Singh and Kehar Singh Sandhanvalia, both of whom commanded troops in Mandi, to retire with their force to the south of the Sutlej. The troops, apprehending treachery on their part arrested both of them and brought there to Lahore where Maharaja Sher Singh kept them under surveillance. In January 1842, they were imprisoned under the orders of the Maharaja and were set at liberty in September 1842 when he granted Atar Singh Sandhanvalia and Ajit Singh Sandhanvalia amnesty and allowed them to return to the Punjab from the British territory where they had taken asylum.

Lahina Singh Sandhanvalia was one of the principal actors in the triple murder on 15 September 1843 which shook the kingdom of Lahore. On the morning of that fatal day, Lahina Singh and Ajit Singh rode out of their mansion with 150 horse and 300 footmen. Lahina Singh hid himself near the garden of Javala Singh, and Ajit Singh went forward to the Baradari of Shah Bilaval, and shot Maharaja Sher Singh dead, pretending to show him the carbine he had received as a gift in Calcutta. The shot was the signal for Lahina Singh to rush with his troops into the garden where the young heir apparent, Kanvar Partap Singh, was engaged in a ceremony distributing alms and, despite the woeful entreaties of the prince, cut off his head with his sword.

Lahina Singh fastened the severed head of Partap Singh to his saddle, and hastened to join his nephew, Ajit Singh. Both of them then proceeded towards the Fort, where, after finishing off Wazir Dhian Singh, they proclaimed minor Duleep Singh as the new Maharaja and Ajit Singh Sandhanvalia as his Wazir. The Khalsa army were aroused to anger and, led by Hira Singh, son of Wazir Dhian Singh, they stormed the Fort early next morning (16 September 1843). Ajit Singh was shot dead while attempting to escape by lowering himself by a rope from the Fort ramparts. Lahina Singh, who had hidden himself in a vault, was seized and gored to death. His mutilated body was, at Hira Singh's orders, fastened to a rope and dragged through the streets of Lahore. Later, it was quartered and pieces of flesh were hung on the gates of the city.

Source: Encyclopaedia of Sikhism, Harbans Singh