It would have been enough if Pragya said to Abhi that she is not pregnant and the doctor lied. If he didn't believe her (there is no reason for him to not believe anyway), she could always prove with another doctor or a pregnancy kit.
Maa could go to Abhi and tell how she had MUed Pragya and she is not really pregnant.
Daadi could share with Abhi that Pragya told her that she is not pregnant.
All this told privately could also lead Abhi to the doctor minus villains knowing it.
Now Abhi may go to the doctor but villains will also go.. just more complications.
I don't understand why do they need to show to the villains that they collected some proof and have Abhi on their side.
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