Director Shonali Bose may well be termed the “mistress of misery.” Her characters, invariably women, have been suffering souls. Whether it be in “Amu,” set in the aftermath of the 1984 anti-Sikh riots, or “Margarita with a Straw” and its story of a teenager with cerebral palsy, Bose’s protagonists have been largely unhappy. Her latest feature, “The Sky is Pink” — unnecessarily long at 159 minutes — is based on the real-life tale of a girl who dies at an early age from complications arising out of an immune-deficiency illness. Aisha (Zaira Wasim) tells us not only her own sad story, but also that of her parents, Aditi (Priyanka Chopra Jonas) and Niren (Farhan Akhtar). When Aditi falls pregnant, she has already lost a child to the disease, but religious compulsion pushes her to go ahead. Predictably, the baby girl, Aisha, develops the same problem. The parents, who live in New Delhi, rush her to London. Since they cannot afford the treatment, which involves a bone-marrow transplant, Niren broadcasts a plea from a radio station that raises a large amount of money. But years later, the bubbly Aisha falls seriously ill, and the effect of her decline on her brother, Ishan (Rohit Saraf), and her parents makes up rest of the plot. “The Sky is Pink” essentially explores the way marriages fall apart after a child gets sick. But Bose weaves into this storyline several distracting features, including Ishan’s budding love affair, which is rocked every time there is crisis in Aisha"s life. Bose’s film could be compared to Mehdi M. Barsaoui’s debut, “A Son.” Set in Tunisia in 2011 after the “Jasmine Revolution,” it also deals with a couple’s turmoil after their son is shot and wounded by a sniper. Barsaoui intelligently scripts how the couple crack under the pressure and their relationship begins to totter. There is not a single scene that is at odds with the plot. In contrast, “The Sky is Pink” digresses into marital jealousy and a string of dramatically charged moments, diluting the core theme. Akhtar, who is an excellent actor, seems out of sorts in this setting, while Chopra Jonas fails to convey a mother’s emotional pain and seems far too dolled up to adequately portray a character in torment. In fact, the only high point is the fine acting by Wasim.