Adolfs half sister, Angela, had 3 children. Angela Merkel would be a daughter of one of these 3. In Germany around that time you would name the children after the grandparents. First born daughter would be named after the mothers mother.
Hitler had a notorious relationship with his niece, Angela Maria Raubal. He was controlling and always had assigned oversight to her.
Why?
She committed suicide at the age of 23 in Hitler's apartment, with Hitler's pistol.