Please see
===Disputed marriage
For evidence that Sir William de Ferrers' wife was a Segrave, see Legge, Anglo-Norman Letters & Petitions (Anglo-Norman Text Soc. 3) (1941): 78–79, for a letter dated 1399/1406 from Thomas la Warre, 5th Lord Warre, to Thomas Arundel, Archbishop of Canterbury, which
mentions his “cousin” [mon tesentierment amé cousin], Henry le Despenser, Bishop of Norwich. Bishop Despenser and Lord la Warre were kin by way of their common descent from the Segrave family.
http://archiver.rootsweb.ancestry.com/th/read/GEN-MEDIEVAL/2008-12/...
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For evidence that the (main) wife of William de Ferrer was not a Segrave, but was Ellen de Menteith, see J. Ravilious, The Earls of Menteith: Murdoch, Earl of Menteith and the Ferrers family of Groby, The Scottish Genealogist (March 2013), Vol. LX, No. 1, pp. 12-25 [https://media.geni.com/p13/bb/fa/cf/28/5344485e789c839d/tsg_the_ear... PDF]
“That William de Ferrers may have married a Segrave lady as his first wife seems quite likely, but the Baddesley Clinton windows should not be taken as proof of this alliance, let alone evidence that this individual was the mother of one or more of William de Ferrers children.”
J. Ravilious
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https://www-personal.umich.edu/~bobwolfe/gen/mn/m26042x26043.htm
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If there’s agreement, then the children of William de Ferrers, 1st Baron Ferrers need to be moved from mother Margaret (or Alice) de Segrave - but her profile would stay connected.