Dolores Umbridge was the first child of a wizard named Orford Umbridge and a Muggle named Ellen Cracknell. Under her father's influence, she despised her Muggle mother and her Squib brother, considering them inferior to her and her father, and Dolores and her father denounced them. Before Dolores reached 15 years old, Ellen and her son returned to the Muggle world, never to be heard of again. At s
ome point, she obtained her wand, made from birch and dragon heartstring with an unusually short length of only eight inches. According to Garrick Ollivander, abnormally short wands usually selected those whose moral character was stunted, rather than because they were physically short. Umbridge attended Hogwarts School of Witchcraft and Wizardry, where she was. Sorted into Slytherin and her head of house was Horace Slughorn. She never got along well with Slughorn, who considered her to be an "idiotic woman" and "never liked her"; also, fellow student and later colleague Severus Snape greatly disliked her as well. She was also never given any position of power (i.e. Prefect, Head Girl) during her studies, which made her feel deprived, and she never truly enjoyed her time as a student at Hogwarts.
