Margaret Fitzbernard was the daughter of Ralph Fitzbernard, of Tong Castle in Kent. 
Her father had acquired the castle through inheritance as a descendant of a descendant of John de St. John and held the estates in 22 Edward I. (1294). Her father died in 34th Edward I. (1306) leaving a son Thomas Fitzbernard, who later (date unknown but after 1310) died without heir. Margaret had married Guncelin de Badlesmere, their son Bartholomew de Badlesmere, at length, succeeded to this manor and castle, as part of his mother's inheritance.
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