Kolkata: Rajashree Birla, who heads the CSR arm of Aditya Birla group, said her son Kumarmangalam was “audacious and always striving for perfection”. “Kumarmangalam is an audacious and hardworking person and always striving for perfection. When he took charge of the group in 1995, the size was $2 billion, which is now $40 billion,” she said at an interaction organised by MCCI here. Terming her husband Aditya Birla as a “true karmayogi”, she said, “I consider him as a my greatest guru in life”.