The Plantagenet Link
Most genealogists would love to find a royal connection somewhere in their lineage - particularly to the House of Plantagenet, who ruled England between 1154 and 1399. Any claim to have found royal Plantagenet ancestry should therefore be treated with a certain amount of scepticism, and the sources of such a claim double-checked for accuracy.
Whitaker's History of Whalley, which details the pedigrees of prominent Lancashire families, indicates that Mary Haydock, who married Peter Ormerod (of Ormerod) in about 1561, was the 5th great granddaughter of Thomas Clifford, 8th Baron de Clifford, who was killed during the Wars of the Roses, at the First Battle of St Albans.
Thomas Clifford was in turn the 3rd great grandson of Edward III, King of England, and therefore a direct descendent of all earlier Plantagenet monarchs and their predecessors.
This would mean that all descendents of Peter Ormerod (of Ormerod) were therefore direct descendants of Edward III, through Mary (née Haydock).
Details of these descendants can be found in the Descendants of Peter Ormerod (of Ormerod) pedigree chart.
Mary's ancestry can be found at Ancestors of Mary Haydock (née Haydock), which contains source details for the information contained within the pedigree chart.