The villainous Grace Edwards
Grace Edwards (Lori Loughlin) is a villainess from Blue Bloods' seventh season opener, "The Greater Good" (airdate September 23, 2016). She is the widowed mother of Louis Edwards, who is training to join the NYPD.
Grace and Louis' brief backstory revealed that her husband, Martin Edwards (an NYPD officer), was killed in the line of duty a decade prior to the episode's events. The pair met with Frank Reagan regarding a memorial ceremony being held for Martin, with Louis' training at the academy being brought up. Afterwards, Grace asked her son to give her and Frank some time alone, and after Louis leaves, Grace stated that she hadn't slept since Louis joined the academy, with Frank offering to do whatever he could to help. To Frank's surprise, Grace turned heel by telling Frank to make sure Louis doesn't graduate; suggesting that he could fail, disqualify, or even eject her son from the academy to make sure he doesn't become a cop.
Grace resurfaced in the episode's climax, coming after he interviewed Louis about his reasons for wanting to join the NYPD. She expressed gratitude after Frank stated that he looked into her son's file and searched for a reason to fail him, but when Frank informed Grace that he wouldn't fail him and that he needed cops like him, the villainess' gratitude became anger. In addition, the callous Grace lashed out at Frank for not doing enough to fail her son, while accusing not only Frank, but her late husband of causing Louis to romanticize the NYPD. Frank's suggestion to Grace that she should accept Louis' decision was met with more anger from the villainess, who uttered the words, "Go to hell," after saying that her son could end up shot and killed just like Martin.