RAJ KAUR (d. 1838), also known as Datar Kaur or more popularly Mal Nakain, was the second wife of Maharaja Ranjit Singh. She was the daughter of Ran Singh Nakai, and was married to the Maharaja in 1798. Though Ranjit Singh married several other women, Mal Nakain remained his favourite. She was the mother of the heir apparent, Kharak Singh. 

She took active interest in the affairs of the State and accompanied her son, Kharak Singh, when he was sent out on an expedition to Multan in 1818. Raj Kaur died on 20 June 1838. S.S.B.

References :

1. Suri, Sohan Lal, Umddt ut-Twarikh. Lahore, 1885-89
2. Ganda Singh, ed., Maharaja Ranjit Singh (First Death Centenary Memorial Volume). Amritsar, 1939