please try to understand the below given chart.
ME ------> my father (X) ------> My grandfather (Y)
SHE ------> her mother (A) -----> her mother's father (B) -------->B's father (C)
Y AND C ARE REAL BROTHERS.
IS THIS RELATIONSHIP LEGAL ACCORDING TO THE LAW ? IF NOT IN HINDU RELEGION, WILL THIS MARRIAGE BE LEGAL IN MUSLIM/ SIKH CULTURE ? KINDLY REVERT.