Billionaire Vivek Chaand Sehgal, Chairman of India's biggest car parts manufacturer Motherson Sumi Systems, said his job is to teach everything that he can to his son and Vice Chairman Laksh Vaaman Sehgal. "I'll retire when I go on four shoulders," the 63-year-old said. Sehgal added when he's around 68, he'll start looking at spending time with his four grandchildren.