Percival Treadaway

Percival Albert Treadaway, Earl of Stillwater (born 1895) is the eldest son of the late Albert Treadaway and his widow Ella Treadaway (nee Roberts), Dowager Countess of Crownmere. He is the current owner of Crownmere Castle in York, and the brother of Christopher Treadaway. He is also the husband of known Shrew, Katherina Treadaway, Countess of Stillwater.

Lady Katherina Treadaway, Countess of Stillwater
Percy Treadaway met Katherina Crawley in late 1922 and was at first cold towards him. As someone to inherit a title, Katherina saw him as nothing more than the other men who she had encountered, arrogant and self-centered. However, at his first visit to Downton Abbey, he showed that he was not those things and they start a courtship. They were engaged by late 1924. By 1927, they are married and expecting their first child together.