Paa is an emotional father-son relationship with the ailment as the back-drop. Unlike real life, the film portrays Amitabh Bachchan as Abhishek Bachchan’s son. Amitabh Bachchan suffers from Progeria, a rare ingrained abnormal characteristics where the person ages rapidly.Is That Movie Director is R, Balakrishan And Music Director is Ilayaraja. This Movie’s Cast & Crew are Amitabh Bachchan, Abhishek Bachchan, & Vidya Balan.