They were indeed a noble race, as their biographer has explained.

Ever fearless in their country's cause, they sneered at the mandates from impregnable Stirling, and were loyal in every generation.
Glencardine was a stronghold feared by all the surrounding nobles, and its men were full of valour and bravery.

One story of them is perhaps worth the telling.

In the year 1490 the all-powerful Abbot of Inchaffray issued an order for the collection of the teinds of the Killearns' lands possessed by the Grahams of Glencardine in the parish of Monzievaird, of which he was titular.

The order was rigorously executed, the teinds being exacted by force.
Lord Killearn of Dunning Castle was from home at the time; but in his absence his eldest son, William, Master of Dunning, called out a number of his clansmen, and marched towards Glencardine for the purpose of putting a stop to the abbot's proceedings.