Hrithik Roshan stars as Rohan in the film Kabhi Khushi Kabhie Gham .
Ten years later , Rohan ( Hrithik Roshan ) returns home from the Boarding School , and accidentally overhears a conversation from his grandmothers ( Achala Sachdev and Sushma Seth ) that Rahul was adopted , and then the reason why Rahul left home , whereupon Rohan vows to reunite the family .
Kabhi Khushi Kabhie Gham...