Baron of Kilton Marmaduke de Thwenge
Marmaduke was born in 1225 in Kilton Castle, Brotton, Yorkshire, England.¹   He died at the age of 54 in December 1279 in Kilton Castle, Brotton, Yorkshire, England.¹ 

 Lucia de Bruce
Lucia was born in 1236 in Skelton Castle, Yorkshire, England.¹ 

 Baron Marmaduke de Thwenge
Marmaduke was born in September 1256 in Kilton Castle, Brotton, Yorkshire, England.² 

 Robert de Thwenge
Robert was born in 1258 in Kilton Castle, Brotton, Yorkshire, England.² 

 Sir John de Thwenge
John was born in 1261 in Kilton Castle, Brotton, Yorkshire, England.² 

 Sir Edmund de Thwenge
Edmund was born in 1263 in Kilton Castle, Brotton, Yorkshire, England.² 

 Alice de Thwenge
Alice was born in 1265 in Kilton Castle, Brotton, Yorkshire, England.³ 

 Margery de Thwenge
Margery was born in 1267 in Kilton Castle, Brotton, Yorkshire, England.²