Right from the beginning Suman was shown to be bitter frustrated woman who hated the other woman and her child while Sujata had always felt a sense of empathy towards the other woman.
So it is not surprising that she descended into this deep pit in her hatred for the other woman
Agree here. Remember her scene with guddi infornt of guddi she said maine ye sab apne bete ke liye kia h n guddi ke jane ke baad she said ki mai tumhe real reason nhi bata sakti tum nhi samhaj paogi. This dialogue of her clearly indicate that theres a highly possibility of twins