sentences:  Then, producer N. C. Sippy, who till then was assisting Bimal Roy and Hrishikesh Mukherjee and penned screenplays of "Khamoshi" (1969) and "Anand" (1971), made his directorial debut with the film.Gulzar bought the rights of the story, and rewrote the screenplay removing the portions he felt were too formulaic and commercial.Meena Kumari was roped in for the lead role of grandmother, she was ailing at the time, and worked through her bad health in the film.