Here is some info on the significant characters, original and canon, who appear in Resolving a Misunderstanding.
Significant Character Dates
This list includes characters’ birth dates (b.) and, where relevant, Sorting year (s.), NEWTs year (n.), death dates (d.), and House, as well as their wand components. The characters are listed in birth order.
Albus Dumbledore: b. 1 August 1840, s. 1851, n. 1858; GRYFFINDOR; Yew, Dragon Heartstring (original wand components, Holly, Unicorn Tail Hair; Transfiguration teacher, Headmaster)
Collum McGonagall: b.1844, s. 1856, n. 1863, d. 1871; GRYFFINDOR; Oak, Phoenix Tail Feather (Merwyn’s father; OC)
Siofre Tyree (McGonagall): b. 1845, s. 1856, n. 1863; RAVENCLAW, Ivy, Thestral Tail Hair (Merwyn’s mother; OC)
Merwyn Marcas McGonagall: b. 1869, s. 1881, n. 1888; RAVENCLAW; Hazel, Phoenix Tail Feather (Minerva’s father; linguist and specialist in ancient spells; OC)
Egeria Egidius (McGonagall): b. 1875, s. 1886, n. 1893; GRYFFINDOR; Holly, Unicorn Mane Hair (Minerva’s mother; Healer-midwife; OC)
Reginald Crouch: b. 1886, s. 1897, n. 1904, d. 1935; GRYFFINDOR; Oak, Unicorn Mane Hair (Gertrude’s late husband; OC)
Valerianna (Crouch) Yaxley: b. 1889, s. 1900, n. 1907; SLYTHERIN; Hornbeam, Unicorn Tail Hair (Gertrude’s cousin; OC)
Gertrude Gamp: b. 1897, s. 1908, n. 1915, SLYTHERIN; Ash, Unicorn Mane Hair (Arithmancer; OC)
Malcolm Mercury McGonagall: b. 1907, s. 1918, n. 1925; GRYFFINDOR; Olive, Jobberknoll Feather (orig. Yew, Unicorn Mane Hair) (Minerva’s oldest brother; curse-breaker, magical pest control specialist; OC)
Morgan Marianus McGonagall: b. 1910, s. 1921, n. 1928; HUFFLEPUFF; Apple, Unicorn Tail Hair (Minerva’s middle brother; editor/publisher; OC)
Murdoch Maxentius McGonagall: b. 1913, s. 1924, n. 1931; RAVENCLAW; Hawthorn, Unicorn Tail Hair (Minerva’s youngest brother, apothecary/Potions master; OC)
Cormac Quinlivan MacAirt, “Quin”: b. 1916 (No School); Oak, Augurey Tail Feather (Minerva’s friend; entrepreneur; OC)
Brennan Sean O’Donald: b. 1917 (Muggle) (Melina’s fiance/husband; chemist/pharmacist; OC)
Robert Gropius Crouch: b. 1919 (Durmstrang); Ebony, Hippogriff feather (Gertrude’s son; OC)
Minerva Morag McGonagall: b. 4 October 1924, s. 1936, n. 1943; GRYFFINDOR; Magical Ivy, Dragon Heartstring
Melina Alexandrina McGonagall: b. August 1936, s. 1947, n. 1954; HUFFLEPUFF; Holly, Unicorn Tail Hair (Murdoch’s daughter, Minerva’s niece; Healer-in-training in RaM; OC)
For a list of almost every character who appears in RaM, and a brief description of each, check out the “Character Guide,” which is available in a separate post.
Albus Dumbledore’s birthdate is based on the date estimated prior to the publication of Book 7.