The big similarity is there was a vampire called Katherine that both brother fell in love with over a century ago and they meet a human,Elena who looks exactly like Katherine...so basically her doppelganger.
In Pyar ki... there's Maithali with who Abhay seems to have a past with who looks exactly like Pia-a human
Also noticed that in TVD some of the vampires can walk in the sun as they have day-rings and in pyar ki... aswell the vampires can walk in the daylight without burning or sparkling.
so i guess these are the creative changes ekta went through with...did she...bringing TVD into her show
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