Edna is the mother of Carl the Evil Cockroach Wizard and Brother Herman. She is a fire-breathing dragon while her sons are a cockroach and an ant. Edna's favorite son is obviously Herman; she always gives Herman compliments, respect, and love while she gives Carl the insults, the belittlement, and occasional love. Edna does know of Carl's desire for her love, and she has used it to get him to do things for her, as revealed in "An Inconvenient Tooth".

It's also revealed in "Mission Yinpossible" 