It seems who her mother actually was is in question per her Wiki page:
https://www.wikitree.com/wiki/Browne-20#_note-13
Research Notes
Hitchin-Kemp gives Eleanor's mother as Margaret Malet;[9] Burke gives the name Mary Malet, daughter of Sir WIlliam Malet, as Eleanor's mother. However, her father's will names a wife Anne _____,[4] who may have been his only wife or she may have been a second wife. According to the Visitation of Surrey, it was Robert's brother, William, who married Mary, daughter of Sir William Mallett.[21]
The page for Anne:
https://www.wikitree.com/wiki/Unknown-277379
Biography
Anne ______ married Sir Robert Browne, son of Sir Thomas Browne and Eleanor FitzAlan. They had one daughter: Eleanor, wife of Thomas Fogge, Esq., and of Sir William Kempe.[1][2]
Anne was living on 9 Dec 1509, when she was named in her husband's will.[1]
Sources
↑ 1.0 1.1 Douglas Richardson, Royal Ancestry: A Study in Colonial and Medieval Families, 5 vols, ed. Kimball G. Everingham. Salt Lake City: the author, 2013. vol. IV, page 279, OLLANTIGH 13.
↑ Douglas Richardson, Magna Carta Ancestry: A Study in Colonial and Medieval Families, 4 vols, ed. Kimball G. Everingham. 2nd edition. Salt Lake City: the author, 2011. Vol. III, page 275, OLLANTIGH 12.