Marmaduke Thweng
Marmaduke was born in 1230 in Yorkshire, Eng.  He died at the age of 64 in 1294 in Derbyshire, Eng.

 Lucia (Lucy) de Brus
Lucia (Lucy) was born in 1240 in Skelton Castle, York, Eng.

 Robert Thweng
Robert was born in 1260 in Kilton Castle, York, Eng.  He died at the age of 19 in May 1279.

 John de Thweng
John was born in 1261 in Kilton Castle, York, Eng.

 Lord Marmaduke de Thweng
Lord Marmaduke was born in 1280 in England.