Katherine Grant, 12th Countess of Dysart (1 June 1918 – 8 November 2011) was a Scottish peeress.
On her mother's death Lady Katherine's elder sister, Lady Rosamund Agnes (1914–2003) became the 11th Countess of Dysart, but never married or had issue; on her death in December 2003 Lady Katherine succeeded to the titles of Countess of Dysart and Lady Huntingtower.
[2] In 1941, she married Lieutenant-Colonel John Peter Grant younger of Rothiemurchus (1915–1987), who succeeded his father as 15th Grant of Rothiemurchus.
They had two children: The Countess died on 8 November 2011, aged 93.
[1][2][3] Her son Johnnie (John Peter Grant) then became the 13th Earl of Dysart while his son James, as heir to the earldom, became Lord Huntingtower.