" ...breaking Albus’s nose at the funeral was not decent. It would have destroyed Kendra to see her sons fighting like that, across her daughter’s body. A shame Gellert could not have stayed for the funeral. . . . He would have been a comfort to Albus, at least."
-- Bathilda Bagshot (DH18)
Ariana Dumbledore, sister of Albus and Aberforth, met her accidental death during a three-way duel between the brothers and Gellert Grindelwald (DH35). According to an interview given to Rita Skeeter by Bathilda Bagshot, the brothers had a “dreadful coffin-side brawl” during the funeral in which Aberforth bloodied Albus’s nose, perhaps breaking it (DH18)
Compare to the graveyard scene in William Shakespeare's Hamlet. -BB