A typical Bollywood Sister in the 80s would go to a temple situated on some remote hill(Kaali Tekdi Kaa Mandir) at about noon time (..or when no one's around). She would take the less travelled path to the temple and her only companion would be her blind mother. A day back she would have told her mother that she just happened to see her brother (..who wud be the hero ) dancing on some R D Burman tune with some aunty ( milf actually , don't ask me, whats a MILF? ... u can substitute it with Asha Parekh, Parveen Babi, Anita Raj ...) in Chota Kashmir (Arrey Milk Colony, Goregaon, Mumbai .. and to save money on travel , for my entire life my father told me that’s KASHMIR and beyond that is Pakistan). She never reveals what was she doing there. If in some movies if she eventually does tell then she tells that she was playing badminton(bad-men-in-town) with other aunties. This aunty would be the just out of college daughter of the enemy of this blind woman.
The hero would be told to go away from the house (How Convenient!!). Then this well fed sister would somehow find the bad man and upon seeing him say something which would sound to my ears like " Mera Bhai teri lega", "Kaisa dhoya tha tereko usss dinn , abhi tak sudhra nahi, saala ","Yeh auraton ka temple hain , namard kahike!!" and something for which she can be sued in this country “Kaali Shakal wale tera dil bhi kala hain”. With this much amount of provocation the villain would do what he eventually does. The blind mother being a widow for a really longggg timee can barely distinguish between moans of pleasure and the pangs of distress and so becomes a witness (..Andhaa Kanoon). Then the hero beats up the villian and the villian agrees to marry the girl.
No one blinks an eye when a child is born exactly 6 months after the temple incident and looks like the villain when he grows up.