By Abigail O’Leary King Charles’s friend Captain Ian Farquhar has died at the age of 78. Farquhar, an accomplished huntsman, reportedly died at the monarch’s Highgrove Estate. Farquhar served as the Queen Mother’s equerry and in the Queen’s Own Hussars, a cavalry regiment of the British Army. Farquhar and Charles reportedly became close friends when William briefly dated Rose Farquhar in 2000 after he finished his A-levels at Eton. Farquhar was Master of the Beaufort Hunt for 34 years. It is the West Country’s oldest and largest fox hunt, who shared a tribute on Instagram reading: “It is with …