The other is " I remain unvanquished" .There were two brothers who headed this clan and they went their seperate ways, hence two motto's
There are many variations of the name including Kerr, Ker, Carr and Carre. These all have links to the Norse 'Kjrr' meaning 'marsh dweller' and the Gaelic 'Caer' meaning 'fortress'. The gaelic 'Ciar' meaning 'dusky' is also a possibility.
The founders of the clan were two brothers, Ralph and John who were of Anglo-Norman background. Disputes caused the clan to break into two branches. These were to be known as the Kerrs of Ferniehurst and the Kerrs of Cessford. The two branches were reunited in 1631, when William Kerr of Ferniehurst was married to the heiress of Cessford.
Ferniehurst Castle still belongs to the chiefs, although the seat of the chiefs stands at the great mansion house of Monteviot.