i feel kunal is meenakshi brother illegitimate or mandir mein kiya hua shadi and parul is his mother
kunal father might have done something grave thats why meenu adopted baby kunal so that he not get affected by his father history as wehave seen how parul not wanted to humiliate mishti in her father mishtake and told baap ke galti ki saza bete ko kyun i feel she understand this as she being mother of even that type of son
anyway meenu i feel from starting was a control freak who would have liked to control people around her abir baba and meenu had love marriage maybe before marriage abir baba used to do everything according to her wishes as u know in start phase of love story it happens but after marriage even meenu wanted her way or no way and abir baba and his family has got fed up with her antics especially abir baba and would have felt suffocated but was doing adjustments due to abir goodwill
as we can see meenu not have other child means abir was atleast five year old when she came to nanu place so they could have gone for second child so may be the reaosn is meenu and her husband relation would be strained he was just somehow wearing with her for abir sake
but due to suffocation and meenu leaving for nanu place would have made him feel more suffocated and he would have seaked outside support like some colleagues or girl friend and would have an illegitimate daughter and when meenu came to know she left him or may be he was with some colleague or friend in compromised position and that colleague might be pregnant with some illegitimate child and when meenu caught him she would have msissunderstood the child to be their and already frustrated abir father would not have told the truth and would have accepted the fact and left abir
in this way they can give abir father justification and pave way for abir full fledged family entry
but i feel abir half sibling will enter with his father may be she would actually be not but in meenu eyes she would be and thus abir would hate his baba first but then would understand his situation
because the kind of person meenu is i dont feelthe changes is overnight if you see she has manipulated even baby kunal from childhood i definetly feel kunal this behaviour with masi is meenu plantation she from childhood have manipulated into thinking parul to be servent and this that
because kunal if u see is okay with everyone except maasi from his childhood because right now i can understand kunal behaviour but in childhood he was same it means he was trained
anyway for mishbir i feel abir has alot shortcon=ming and i dont feel he is right for mishti the kind of person abir is he might leave mishti when he want to flee as he has habbit of fleeing from truth the kind of partner mishti want abir has simply only not that quality mishti want a partner who would not leave her at any cost but abir i dont feel would hesistate right now its just pehla pehla pyaar