Mentioned in Whybrow's 1911-20 list of artists in and around St Ives. From Census data it has been possible to identify Katherine as the younger sister of Charles E STIFFE.  Katherine was born in Wales, the daughter of landscape artist and architect John Gilbee Stiffe and his wife.

Katherine grew up in London and was schooled there. As yet her art training is unknown, but she is recognised by Johnson & Greutzner as a floral artist, exhibiting between 1904 and 1939. In 1881 she was a scholar living with her family in South Hampstead, London (154 Alexander Road) and in 1904 her sending-in address for exhibitions was in Folkestone, Kent where she had settled with her unmarried sisters, Maria and Helena.

By 1913 she had moved to Lelant in Cornwall and from 1927 to Launceston, Cornwall, where her sister Helena had died two years previously. In 1928 she had moved to Uckfield and in 1932 to Horsham, Sussex.