sentences:  He was the youngest of the nine children of Ivor Bertie Guest, 1st Baron Wimborne (1835–1914) and his wife Lady Cornelia Henrietta Maria Spencer-Churchill (1847–1927), daughter of John Spencer-Churchill, 7th Duke of Marlborough, aunt of Sir Winston Churchill.The Guest family were wealthy industrialists whose interests included the fastenings-manufacturing company Guest, Keen and Nettlefolds (now known as GKN).Three of Oscar's brothers (Henry, Ivor and Freddie) were also MPs, as had been their grandfather John.