From the short story (and anthology containing it) DONNY DOESN'T LIVE HERE ANYMORE :Donny acted like he didn’t hear me. “You can’t send your mom off into eternity looking like that, Artie. She wouldn’t like it.” He reached into my mother’s casket, shoved his fingers into her mouth like it was the most logical thing in the world.
“Donny, you can’t --!”
“I’m just making her look right, Artie. It’s what she would want.” He tugged hard at my mom’s lips. I knew they were cold because I had kissed them a few moments earlier, and for a moment I felt convinced my friend had completely lost his mind. But when I looked inside Mom’s casket I knew Donny had done something only a best friend would think to do. My mother was smiling again. And she looked just the way I remembered her, the way I would always want to remember her. I got so choked up I couldn’t talk for a few minutes. 
Finally I managed, “My mother always told me you could make her smile.