Khan is married to two ladies concurrently. His first marriage was to Sushila Charak, a Hindu Rajput, on 18 November 1964. Sushila's father, Baldev Singh Charak, was a Hindu Dogra Rajput from Jammu, while her mother was a Maharashtrian Hindu lady.  Khan and Sushila/Salma have four children together; three sons, Salman , Arbaaz and Sohail , and one daughter, Alvira Khan Agnihotri . In 1981, Khan married actress Helen Richardson , a Christian lady whose father was Anglo Indian and mother was Burmese . Some years later, they adopted a girl named Arpita, daughter of a homeless woman who died on a Mumbai footpath.   
Raag is a very complex consists of characteristics like Swar,Thaat,Jaati,Vaadi and use of any characteristc in greater measure changes the complexion ofnthe song.
Similarly,Sur,Laya and Taal are parts of construction of a song.
In other words,Raaga of the songs may be same,but any component used in excess makes the songs sound different and conversely,same components in same Raaga makes the songs sound similar,sometimes almost the same tune too !
This can happen in Mukhda,Antara or Both in 2 is why some songs sound similar from different movies and even different Composers.(and it is branded as a ‘copy’).