Polak, Węgier dwa bratanki

From Poland: The First Thousand Years, by Patrice M. Dabrowski (Cornell University Press, 2014), Kindle pp. 74-75:

But the Hungarian and Polish king found himself in the same situation as had Kazimierz. He too had no male heir—only daughters, and these were born to him late in life. They included the previously mentioned Maria and her younger sister, Hedwig. (An older sister, Catherine, also figured in the picture until her death in 1378.) As already noted, Maria was betrothed to Sigismund of Luxemburg, whose father was king of Bohemia as well as Holy Roman Emperor. Hedwig—born only in the year 1374—also awaited a princely husband, having been promised in marriage since early childhood to Wilhelm of Habsburg.

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All of this might have been enough to inspire a degree of friendliness between Hungarians and Poles. Historically they were on good terms. They did not figure as much of a threat to each other, as they were both just one step removed from Bohemia and the Holy Roman Empire. The Carpathian Mountains served as a boundary between the two countries, but it was a porous one. There was much contact across that border. Furthermore, it is important to note, the clanlike structure and the substantial role played by the nobilities in the two countries were similar. It is not for nothing that, even today, Poles know the ditty “Polak, Węgier dwa bratanki—tak do szabli, jak do szklanki” [emphasis added] (The Pole and the Magyar like brothers stand / Whether with sword or with tankard in hand), whereas the corresponding Hungarian rhyme affects the same brotherly affection for the hard-fighting—and drinking—Poles. (The verse, however, dates from a much later period.)