Guy de Dampierre married twice, first to Mathilde, dame de Béthune with 8 children:
1) Robert III de Flandre, seigneur de Béthune, comte de Nevers
2) Guillaume IV "Sans Terre" de Dampierre, heer van Dendermonde
3) Jean of Flanders, Bishop of Metz and Bishop of Liege (no Geni profile)
JEAN de Flandre ([1250]-Anhève 14 Apr 1292, bur Flines-lez-Raches). The Genealogia Comitum Flandriæ names (in order) "Robertum, Willelmum, Iohannem episcopum Leodiensum, Balduinem et Philippum" the sons of "Guido…ex Mathilde filia Roberti Tenremontensis"[682]. The Annales Blandinienses record the death in 1291 of "Iohannes, filius Guidonis comitis Flandrie et Mathildis de Bethunia eius coniugis, episcopus Leodiensis" specifying his burial at "Felinis" {Flines-lez-Raches, near Douai}[683]. Provost of St Donat at Bruges 1270. Provost of St Pierre at Lille 1274/77. Bishop of Metz 1279. The Gesta Episcoporum Mettensium (Continuatio) records the succession of “filius comitis Flandrensis dominus Johannes” who was later transferred “ad Leodiensem ecclesiam”[684]. Bishop of Liège 1282. A letter dated 13 Oct 1291 bears his seal[685]. The Biographie Nationale de Belgique records his death 14 Apr 1292 at Anhève but does not cite the corresponding primary source[686]. The early 17th century artist Antoine Succa sketched some details of his monument[687
MARGUERITE de Flandre ([1251]-3 Jul 1285, bur Brussels Franciscan Church). The Genealogia Comitum Flandriæ refers to the three (unnamed) daughters of "Guido…ex Mathilde filia Roberti Tenremontensis", specifying that one (listed first) married "Iohanni duci Brabantie"[688]. The Genealogia Ducum Brabantiæ Ampliata names "Margaretam filiam Guidonis comitis Flandrie" as the second wife of "Iohannes dux Lothoringie et Brabantie"[689]. The Oude Kronik van Brabant records that "Johannes primus…in ducatu Lotharingie et Brabancie" married secondly "Margareta, filia Guidonis comitis Flandrie"[690]. The Annales Blandinienses name "Margaretha duxissa Brabantie, filia Guidonis comitis Flandrie" when recording her death in 1284 and burial in Brussels[691]. Betrothed (Papal dispensation 6 Aug 1266[692]) to PIERRE de Bretagne Seigneur de Dinan, Léon, Hédé, Hennebont et La Roche-Derrien, son of JEAN I Duke of Brittany & his wife Infanta doña Blanca de Navarra [Champagne] (Châteaulin, Finistère 2 Apr 1241-Paris 19 Oct 1268, bur Paris, église des Cordeliers). m (1273) as his second wife, JEAN I “the Victorious” Duke of Brabant, son of HENRI III "le Pacifique/le Débonnaire" Duke of Brabant & his wife Alix de Bourgogne [Capet] (Brussels 1253-Antwerp 3 May 1294, bur Brussels Franciscan Church).
(She had 4 children with Duke Jean I of Brabant: Godrey, Jean/John, Margaret, and Marie.)
7) Beatrix de Dampierre, gezegd Beatrijs van Vlaanderen
8) Philippe de Dampierre, conte di Teano
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Secondly, he married Isabelle de Luxembourg and with her he had another 8 children:
(His second daughter named Marguerite, on Geni has been incorrectly split into three [3] separate individuals.)
MARGUERITE de Flandre ([1265?]-after 17 Oct 1327, maybe 1331?). The Liber Pluscardensis records the marriage at Roxburgh in 1279 of "Alexander filius Alexandri tercii et…Margaretæ sororis Edwardi Langschankiæ regis Angliæ" and "filiam comitis Flandreæ"[726]. The Extracta ex Cronicis Scocie records the marriage "apud Roxburgh…dominica proxima post festum Martini" of "Alexander filius regis Alexandri" and "filiam comitis Flandrie" and the celebration which lasted 15 days, adding that she returned to Flanders after her husband died[727]. The Kronik van Arent toe Bocop records that "Rennolt…grave van Gelre" married secondly "dye dochter van dye grave van Flanderen", naming her "Mergreta" in a later passage[728]. The contract of marriage between "Renauls cuens de Ghelre et dus de Lemburgh" and "Guyon conte de Flandre et marchis de Namur et…dame Ysabel se feme…et noble damoisel Margherite fille dou conte et delle contesse devant ditte" is dated 21 Apr 1286[729]. Pope John XXII permitted "nobili mulieri Margarete relicte quondam Raynaldi comitis Gelrensis" to choose her own confessor, dated 17 Oct 1327[730]. The Kronik van Arent toe Bocop records that "dye gravinne van Gelre, Mergreta dochter van Flanderen" died in 1321 [incorrect date, should be 1331?] and was buried "toe Groenendaell"[731]. m firstly (Roxburgh 1279 or 15 Nov 1282) ALEXANDER Prince of Scotland, son of ALEXANDER III "the Glorious" King of Scotland & his first wife Margaret of England (Jedburgh, Roxburghshire 21 Jun 1264-Lindores Abbey, Fife 28 Jan 1283, bur Dunfermline Abbey, Fife). m secondly (Namur 3 Jul 1286) as his second wife, REINALD I Graaf van Gelre, son of OTTO II Graaf van Gelre & his second wife Philippa de Dammartin (-9 Oct 1326)
2a) Johanna de Namur
(Johanna was a nun, and aka Jeanne.)
3a) Beatrix van Vlaanderen "Beatrix van Dampierre"
4a) Jean de Flandre, Comte de Namur
5a) Guy of Namur
6a) Henri de Flandre, comte de Lodi
(The youngest, aka Philippine de Flandre, had been betrothed to King Edward II but never actually married, apparently.)
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About the second Marguerite: She had 5-6 children with her second husband (as his second wife). Two are missing Geni profiles (Guido and "Philipp", but the latter is probably a misspelling of their daughter Philppa, so it is very questionable).
The big problem is with her first husband Alexander Armstrong II 1st Laird of Mangerton Castle who is only connected with one of the three duplicates (the other duplicate has Armstrong children and another child, but no husbands).
ALEXANDER (Jedburgh, Roxburghshire 21 Jun 1264-Lindores Abbey, Fife 28 Jan 1283, bur Dunfermline Abbey, Fife). John of Fordun’s Scotichronicon (Continuator) records the birth "apud Jedword XII Kal Jan" in 1264 of "regi Alexandro filius, paterno nomine vocatus"[660]. The Liber Pluscardensis records the death "apud Lundoris" in 1283 of "Alexander filius Alexandri tercii et…Margaretæ sororis Edwardi Langschankiæ regis Angliæ" aged 20 and his burial "apud Dunfermlyng cum fratre"[661]. The Extracta ex Cronicis Scocie records the death "in festo Sancte Agnetis secundo" in 1283 of "Alexander filius regis Alexandri" aged 20 and his burial "in Dunfermling"[662]. m (Roxburgh 15 Nov 1282) as her first husband, MARGUERITE de Flandre, daughter of GUY de Dampierre Count of Flanders & his second wife Isabelle de Luxembourg (-after 17 Oct 1327, maybe 1331). The Liber Pluscardensis records the marriage at Roxburgh in 1279 of "Alexander filius Alexandri tercii et…Margaretæ sororis Edwardi Langschankiæ regis Angliæ" and "filiam comitis Flandreæ"[663]. The Extracta ex Cronicis Scocie records the marriage "apud Roxburgh…dominica proxima post festum Martini" of "Alexander filius regis Alexandri" and "filiam comitis Flandrie" and the celebration which lasted 15 days, adding that she returned to Flanders after her husband died[664].
She married secondly (Namur 3 Jul 1286) as his second wife, Reinald I Graaf van Gelre. The Kronik van Arent toe Bocop records that "Rennolt…grave van Gelre" married secondly "dye dochter van dye grave van Flanderen", naming her "Mergreta" in a later passage[665]. The contract of marriage between "Renauls cuens de Ghelre et dus de Lemburgh" and "Guyon conte de Flandre et marchis de Namur et…dame Ysabel se feme…et noble damoisel Margherite fille dou conte et delle contesse devant ditte" is dated 21 Apr 1286[666]. Pope John XXII permitted "nobili mulieri Margarete relicte quondam Raynaldi comitis Gelrensis" to choose her own confessor, dated 17 Oct 1327[667]. The Kronik van Arent toe Bocop records that "dye gravinne van Gelre, Mergreta dochter van Flanderen" died in 1321 [incorrect date, should be 1331?] and was buried "toe Groenendaell"[668].
Marguerite's first husband was the son of King Alexander of Scotland, and on Geni his ancestry is all wrong. He is in fact a duplicate of Prince Alexander of Scotland who has been erroneously identified as the partner of a fictional maid of Flanders, Margaretha van Vlaanderen
But the point is, besides marrying Marguerite of Flanders (not "Rebecca") -- he was barely 20 years old when he died. And there is no evidence to my knowledge of him ever having ANY children with her or anyone else. I would feel a lot better if all of this got repaired as soon as possible. And since many of the profiles involved are not MPs, I might be able to do most of the work myself.
https://fmg.ac/Projects/MedLands/FLANDERS,%20HAINAUT.htm#Marguerite...
https://fmg.ac/Projects/MedLands/SCOTLAND.htm#Alexanderdied1283