Rosier was the surname of an old pure-blood wizarding family, and one of the Sacred Twenty-Eight. The family possibly originated in France. They were related to the wizarding Lestrange, Perrot, Gage, Black, and Malfoy families and the Muggle Tonks family, and more distantly to the Lupin and Greengrass families. Also, the female line also continues, at least illegitimately, through the Riddle family, of Muggle origin but with some magical members. Given these relations, as well as the participati