The Hon. Peregrine David Euan Malcolm Moncreiffe, later Moncreiffe of that Ilk, Baron of Moncreiffe and Easter Moncreiffe and Chief of Clan Moncreiffe (born 16 February 1951), is the second son of Sir Iain Moncreiffe of that Ilk, 11th Baronet Moncreiffe and Diana Denyse Hay, 23rd Countess of Erroll. He is also the younger brother of Sir Merlin Sereld Victor Gilbert Hay, 12th Baronet Moncreiffe, 24th Earl of Erroll and Chief of Clan Hay.