Last Watch (2017)

Janet Jupiter is an ordinary young woman who has always lived in the shadow of Holly and Emily, her superhero mother and sister. Holly was Hour Lass, a superhero with a watch that could freeze time, Emily was her sidekick, and Janet was Janet. Super-heroism was never really her thing. Then Emily gets killed in action, Janet and Holly grow even further apart, and each deal with the grief in their own way. But when Holly begins to develop symptoms of Alzheimer's, Janet discovers she is the only one able to retire her mother before she becomes a danger to the very people she's trying to save.