she she had grew up with the Shekars maybe they may have even stronger bond...because they are more because women in the family are shown to be as important as the men...unlike the the Singhs.
but you are right Bhairon can not be replaced...because Alok's character is not show is strong and influential as Bhairon's...maybe if it was Bhairon, Sanshi would have been given a heart to heart talk...and if it does not work, she would have gotten a wonderful slap. Bhairon would have been the one to talk like Shiv did...Shiv wouldnt have to fight his sister...his daddy will be there for that. But what can i say every family have only one Bhairon...and for the Shekars, Shiv is their Bhairon.
but dont worry the Singhs are not going anywhere it will be like "YEH RISTA KYA ..." where the two family's story line will continue.( i hope so)