John Ravilious wrote in 2003 of her marriage and children:

1.6 Mary le Bigod[9]
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identified as a benefactor to the Church of St. Cuthbert,
   Durham (Liber Vitae, vol. 13 p. 107 cited by Rosie Bevan)[7]

Spouse: Ranulf Fitz Robert[9]
Death:  bef 7 Dec 1252[2]
Father: Robert Fitz Ralph (-<1206)
Mother: Hawise de Glanville (-?1194)

Children:   Ralph (-~1270)

1.6.1a Ralph Fitz Randolf*
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Death:  abt 1270[9]

of Middleham, co. York
also held Spennithorne, co. York (inheritance of his son by
   Bertrama) [2]

Spouse: Anastasia de Percy
Death:  aft 1271[3]
Father: William de Percy (ca1193-1245)
Mother: Joan de Briwere (-<1233)

Children:   Joan (-ca1310)
                Mary (-<1320)

Other Spouses Bertrama

1.6.1b Ralph Fitz Randolf* (See above)
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Spouse: Bertrama[2]

Children:   Ralph (-<1316)

Other Spouses Anastasia de Percy
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