Bollywood megastar Amitabh Bachchan, who plays a 12-year-old progeric in "Paa", says he has taken cues from his grandchildren to adapt a child's mannerisms for the role.

"A lot of prosthetics went into making me look like a 12-year-old in 'Paa'. I did try to watch kids and took a little bit of hints from my own kids' childhood, but I took most from my grandchildren. They were quite an inspiration for me for 'Paa', " said Amitabh.

The actor, who turned 67 recently, has essayed the role of a child suffering from progeria, a rare disease which causes premature ageing among children.

Directed by R. Balakrishnan, the film also stars Abhishek Bachchan, who plays Amitabh's father in the film.