They may be thinking that causing rift in the sisters would boost TRP's as everyone will be watching how they will patch up and the rift would provide mirch masala.
I just hope they realize they are so wrong if they are thinking along those lines, in fact the better track would have been to use the bonding b/w Sadi / Ragi to improve the relationship b/w Vasu Ambika.
Hint to this was given when Ragi came home to RajVanch house as a bride and was asked to touch Sadi's feet and Sadi hugged her and Vasu and Ambika were both looking.