This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Broken Blossoms
Lucy's life is such a downer that she has to manually push the corners of her mouth up in order to smile.
Nearly a hundred years later, the closet scene is still gutwrenchingly shocking to modern audiences. A Variety reporter invited to sit in on the second take had to excuse himself to vomit. Griffith himself was shaken by her performance. It would have been even worse if there had been sound: Lillian Gish's screams were so horrific and so loud that people outside the studio thought the actress was in genuine trouble and had to be prevented from rushing in to help.
At the end, Lucy dies at her father's hands. Chen kills him and then himself.
And, just before she dies, she pushes the corners of her mouth in order to smile one last time, while clutching the doll Chen gave to her.