Born on October 11, 1942, Amitabh Bachchan's real surname is Shrivastava. His father, acclaimed poet Harivansh Rai Bachchan, had adopted the pen name 'Bachchan'. 

After which, the family adopted this surname. Big B was initially named Inquilaab, inspired by the phrase Inquilab Zindabad.

This is a rare picture of Amitabh Bachchan surrounded by the kids of the 'Bachchan' family, who came to see him when he was recuperating in the hospital. We take a look at some more photos from Amitabh Bachchan's family album.

A rare picture of the Bachchan family, including late Teji Bachchan and late Harivanshrai Bachchan.

Amitabh Bachchan looks adoringly at Shweta Bachchan in this rare picture

Amitabh Bachchan's son Abhishek Bachchan with wife Aishwarya Rai Bachchan and granddaughter Aaradhya Bachchan, when she turned 1.

A grown-up Aaradhya Bachchan with her dear grandfather

Three generations - Abhishek Bachchan, Amitabh Bachchan and late poet Harivansh Rai Bachchan.

A young Abhishek Bachchan and Shweta Bachchan give a peck on their daddy dearest's cheeks.

Abhishek Bachchan accompanies his father Amitabh Bachchan to an event in this vintage picture.

Abhishek Bachchan shows his new phone to his parents Amitabh and Jaya Bachchan.

Happy Birthday Amitabh Bachchan!