Marmaduke de Thweng , Lord of Kilton, MP, Sir
Marmaduke de was born about 1234 in Kilton Castle, Cleveland, Yorkshire, England.  He died after 1294 in Castleton Castle, Derbyshire, England.

 Lucy de Brus
Lucy de was born about 1234 in Skelton Castle, Yorkshire, England.

 Robert de Thweng , of Kilton, Sir
Robert de was born about 1255 in Kilton Castle, Cleveland, Yorkshire, England.  He died in 1284 in Kilton Castle, Cleveland, Yorkshire, England (dvp & dspm).

 Marmaduke 1st Baron de Thweng , of Kilton
Marmaduke 1st Baron de was born in September 1256 in Kilton Castle, Cleveland, Yorkshire, England.  He died at the age of 66 on September 28th, 1322.

 John Thweng , of Cornburgh, Sir Knight
John was born about 1261 in Kilton Castle, Cleveland, Yorkshire, England.  He died on December 2nd, 1330 in Cornborough, Malton, North Ride Yorkshire, England.