She was born Katharine Ingrid Mary Isabel Ramsay in Edinburgh, Scotland. Her mother, Lady Saltoun, is the suo jure Lady Saltoun and the Chief of the name and arms of Fraser. Her father was great-grandson of Queen Victoria through his mother Princess Patricia of Connaught.
As the eldest daughter without any brothers, Fraser is the heiress-presumptive to the Chiefship and the Lordship held by her mother. Since one cannot become the chief of a clan without taking the clan's surname, Lord Lyon King of Arms recognized her use of the surname Fraser in 1973.
On 20 April 2005, Fraser was appointed a Deputy Lieutenant of Aberdeenshire.