This is what Wikipedia has on Joy Mukherjee who passed away at 1 pm at Mumbai's Lilavati hospital.  

Joy Mukherjee (born 24 February 1939, died 09 March 2012) is the son of Sashadhar Mukherjee and Sati Devi.

His father was a successful producer and a co-founder of Filmalaya Studios.

His paternal uncle is director Subodh Mukherjee, whilst his maternal uncles were Ashok Kumar and Kishore Kumar.

His brothers are Deb Mukherjee and Shomu Mukherjee.

Shomu is married to actress Tanuja & their daughters are actresses Kajol and Tanisha.

His niece is Rani Mukerji and nephew is director Ayan Mukerji.

Joy Mukherjee's aunt Monmaya Devi was daughter of GC Banerjee and Smt Annapurna Devi - then owner of Happy Valley Tea Estate in Darjeeling whose family still run the estate to produce one of the best tea in the world.