One of the most notable members of the Baillie family was the 6th Baronet of Polkemmet, Sir Adrian. He was Deputy Lord Lieutenant of West Lothian and Justice of the Peace. He was Unionist MP for the Linlithgowshire constituency between 1931 and 1935. He married Cecilia (Olive) Wilson-Filmer, the eldest daughter of Lord Queensborough. She reputedly had an income of around £50,000 pounds per year from her grandfather William Collins Whitney, an American multimillionaire. As an MP, Sir Aidrian then spent more time in London and Leeds Castle in Kent. The Baillie family ceased to be resident at Polkemmet from around this time.