As Churchill's father, Lord Randolph Churchill, was the surviving second son of the 7th Duke of Marlborough, his arms should have been differenced, by strict heraldic rules, with a mark of cadency. Traditionally, this would have been a heraldic crescent. Those differenced arms would have been inherited by Winston Churchill. This never seems to have been used by Lord Randolph or Winston. As arms are used to differentiate two bearers, there doesn't seem to have been any confusion between Churchill's arms as a gentleman with many decorations and later Knight of the Garter, those of his brother as a plain gentleman, and his cousin, the Duke of Marlborough, which were adorned with the insignia of a duke. As a Knight of the Garter, Churchill was also entitled to supporters in his achievement. But, he never seems to have got around to applying for them.