My Grandfather is Clarence Charles Turnbull Pereira born 2nd July 1860 Patna Bengal. He is recorded as a Master Builder for The East Indian Company. Married 1911 to Kate Madeline Young. My mother Phyllis May Duncan Pereira was born in Kolkata India in 1912. Sadly her father Clarence Charles died a year later and my mother was put into a Raj Convent school at some point. My mother Phyllis May Duncan Pereira is then found in London in 1948 living in Kensington Square Gardens and has managed to drop her last name Pereira and be known as Phyllis May Duncan. How has she legally been able to remove her last name? Pereira and be known as Duncan. She even married under the name Duncan.