I doubt Sunny will be back . He is not related to Abhi-Pragya so the makers will not care about him. Kiara has high chances of returning as negative.
Given the purab-aliya angle they showed, it seems for sure disha and sunny will be back eventually, but I believe this will happen after prachi and pragya are back in abhi's life and mehra house, because I think ekta and her writers won't want to cram all potential interesting tracks together. Once abhigya and their daughters are united, pragya will get to know about disha-purab-aliya angle obviously when she will be socked to know about purab-aliya being married and aryan being their son, so eventually purab and disha's track will be back.
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