Honestly, I'm 70% sure that this is all Avni's doing, to get rid of a useless obstacle named Ahir while at the same time: 1) create issues between Kalma and get Malhar's support, 2) further provoke Sarthak against the Deshmukhs, 3) get Pillu out of the way in her quest to get her hands on the Rane wealth all to herself by once again EBM Sarthak to force Malhar so that the latter marries her.
Because if you notice, the same Malhar who didn't give a d**m about Avni and her kid, is now vowing to protect them and punish whoever killed Ahir... I mean, all this emotional investment out of nowhere when he barely tolerated her a while back?
I get that tragedies affect people, but Avni is also doing her part, by taking full advantage of it.
And second, dunno if I'm the only one who noticed it, but Avni had an "interesting" look at some point in the 13th Nov episode.