R Balakrishnan's 'Paa' will see AB Junior playing father to the Big B. It's amazing how films give such opportunity to actors,  Amitabh Bachchan has delivered several heart touching performances and the next one from this superstar is his character of a 12-year-old progeria patient in 'Paa'.

Bachchan says, to get the right look, he had to stick on several pieces of specially crafted clay. To get the perfect look for the character, international make-up artist Stephan Dupuis was roped in, who did Robin Williams' make-up in 'Mrs. Doubtfire'.

Bachchan keeps his blog updated and now that this movie is complete, he could not wait to upload the first poster of the film. Abhishekh and Vidya play parents to the Big B, suffering from progeria, an extremely rare, severe, genetic condition wherein symptoms resembling aspects of aging are manifested at an early age. Approximately one in four million people are diagnosed with this condition.

"The face that you see is the result of deep research. Kids affected by this problem lose all their hair, become bald and their veins begin to show prominently on their heads, which enlarge to a size beyond normal. Their teeth and eyes suffer also...," posted Amitabh.  'The prosthetic process is arduous...Around eight pieces specially designed through laborious clay models are most meticulously stuck on to the face. Once the make-up starts, it is impossible to move even a few centimetres. Eating and drinking has to be avoided and you cannot talk because it displaces the pieces over the contours of the face. Separate pieces form the entire look,' the actor posted.

Paa, a sensitive story about the relationship between a politician-father and ageing and ailing son is slated for release on December 4.