The only son of George Charles, 4th baron Vernon, and his wife, Frances Maria Borlase-Warren (who later dropped the Borlase from her maiden name), George John Vernon succeeded his father as 5th baron in 1835. He was married on 30 October 1824 to Isabella Caroline Ellison [d. 1853]; they had two sons (a third died in infancy) and two daughters. He assumed by sign-manual in 1837, in compliance with the will of the Viscountess Bulkeley, the surname and arms of Warren only. On 14 December 1859, he was married a second time, to his cousin Frances Maria Emma Boothby. George was succeeded in the barony by his eldest son, Augustus Henry.