If Dev was missing during Sonakshi's delivery or when Soha was born or during her labor days then whose is responsible for this ? Was Dev responsible for not being there .As per the flashback,Sona decided to tell Dev about Soha only when she was 6 months old so before that she never bothered to inform Dev about his child .If Dev has missed all this it's not because of his carelessness but because of Sonakshi.
If she hated him so much after the fight that she didn't want to shate the news with baby's father then why give birth to his child and then fail to inform him? Here Sonakshi is legally and morally wrong for keeping Dev in dark about her pregnancy.When will she realize this mistake of hers ?
My only advise to Dev is ,you should have been shameless n insensitive.After the breakup you should have taken her to a doc to get her checked to see if Shimla night worked or not .Looks like it was not Sonakshi's duty to inform you about pregnancy but ur job to find out the truth .
I am sure if a Dev had hidden the child from her then he would be in jail for separating the mother and the child but it's Sonakshi Bose and she is perfect n can never be wrong .