Shizuka Hattori

Shizuka is Heiji's mother, a fact that shocks Kogoro, Ran, and Conan, due to her incredibly youthful appearance. Heiji is the only one who insults her looks, calling her "old lady." Nonetheless, Shizuka is very supportive of her son, rooting for him to solve cases, though she sometimes calls her husband, Heizo Hattori, police chief of Osaka, to assist Heiji. She is skilled in kendo.
(Source: Detective Conan Wiki)