I don't get how this vansh logic goes.
In naagin 2 - it was mentioned that there are only 7 vansh.
According to today's ep - only one 5 of the naag vansh can be a shesh naagin.
Shesh, takshak, .?..,..?.., Vashuki.
In naagin 3,4 - we got nidhok - sumitra, vikrant and kalkuth - vishakha.
But how mehak can be from vashuki vansh when their mom, sis and grandmother is from shesh vansh.
I also thought vishakha is shesh vansh but it was than revealed in n4 that she is from kalkuth vansh.
So does any naagin can go to another vansh by their own will like our prime example : Sesha - shesh -> takshak -> kusarp/kalkuth -> shesh