Her father was William De Hasting
https://fmg.ac/Projects/MedLands/ENGLISHNOBILITYMEDIEVAL3D-K.htm#_T...
Her father was William De Hasting
https://fmg.ac/Projects/MedLands/ENGLISHNOBILITYMEDIEVAL3D-K.htm#_T...
Go down that page (or do a find on Pecche)
HENRY de Hastings, of Ashil, Norfolk, son of WILLIAM [III] de Hastings & his wife Margery Bigod of Norfolk (-before 9 Aug 1250). King Henry III granted "custodia terre et heredis Willelmi de Hasting" to “...Isabelle que fuit uxor Osberti Giffard et Matildi sorori ipsius Osberti”, dated 1229[819]. King Henry III granted rights relating to "priori et sacriste Sancti Edmundi" to “Henrico de Hasting senescallo domus sue” as previously held by “Willelmus pater suus”, dated 1229[820].
m (before 7 Jun 1237) ADA of Huntingdon, daughter of DAVID of Scotland Earl of Huntingdon & his wife Matilda [Matilda] of Chester (-after 1241). The Annales Londonienses name "Margaretam, Isabellam, Matildam, et Aldam" as the four daughters of "comiti David", recording the marriage of "la tierce fille Davi" and "sire Henri de Hastinges"[821].
Henry & his wife had [four] children:
4. [MATILDA de Hastings (-London [1264/65], bur Sainte-Marie ---). The Liber Memorandorum Ecclesie de Bernewelle names "Matildis de Hastinges" as the first wife of "dominus Gilbertus Pecche", adding that she died in London and was buried "in ecclesia canonicorum beate Marie ultra aquam" as burial in England was not possible because of "perturbacionem que tunc erat" (suggesting her death in [1264/65][1689]. The source does not name her parents. The Complete Peerage suggests that she was one of the three (unnamed) unmarried daughters of Henry de Hastings who are mentioned as living on Henry’s death in 1250[1690]. m as his first wife, GILBERT Pecche, son of HAMO Pecche & his wife Eva --- (-25 May 1291).]
Just to be slightly clearer, because it’s a lot of text.
WILLIAM [III] de Hastings (-[Jan 1226]). m MARGERY Bigod. His son was:
HENRY de Hastings, of Ashil, Norfolk, m (before 7 Jun 1237) ADA of Huntingdon, daughter of DAVID of Scotland Earl of Huntingdon & his wife Matilda [Matilda] of Chester (-after 1241).
Henry & his wife had [four] children:
1. HENRY de Hastings (-before 5 Mar 1269). m JOAN de Cauntelo, daughter of WILLIAM [IV] de Cauntelo of Calne
2. MARGERY de Hastings .
3. HILARIA de Hastings m ([before early 1256]) as his second wife, WILLIAM [II] de Harcourt, son of RICHARD [I] de Harcourt & his wife Orabilis de Quincy
4. [MATILDA de Hastings (-London [1264/65], bur Sainte-Marie ---). m as his first wife, GILBERT Pecche, son of HAMO Pecche & his wife Eva --- (-25 May 1291).]
So Matilda was daughter of Henry, and also, sister of a Henry.