The Ellerkers of Ellerker pose a problem for researchers as the eldest son was usually named Ralph. The son of your Ralph Ellerker took part in the Pilgrimage of Grace (1536) as a friend of Robert Aske, the Captain of the rebellion. Ralph Ellerker the elder had been asked by Henry VIII to put down the rebellion and hold the city of Hull, so he was not impressed to see Ralph Ellerker, junior along with Robert Bowes presenting the articles of protest at the royal courts. Henry told him that he should not trust the word of a 'common pedlar of the law'(Aske). His position, seen as neither a true rebel nor loyalist saved his neck when the Pilgrim leaders lost theirs. PS - Aske was staying at the Ellerkers when he heard of the uprising in Lincolnshire. Hope this is of use to you.