My wife Cathy and I went to a production of Mamma Mia! at the local high school today. We didn’t know what to expect, but the performance turned out to be excellent. I was a little surprised—after all, high school musicals can be uneven—but what really stunned me was how emotional I got, not only because of the play itself but also because of the sentiment it touched in my own life.

As many of you probably know, the premise of the show is a daughter’s wedding to which she’s invited three men. She believes that one of them may be her father. All three of them show up, and the songs of ABBA tell the story. There are moments of hilarity, and there are moments of joy, and there are bittersweet moments of genuine emotion such as when the bride’s mother sings to her daughter on the day of the wedding. The mother sings a song about time slipping away as the daughter grew from a schoolgirl to a woman about to be married. That one left me a little teary-eyed. It reminded me of when I was nineteen, and I got married for the first time (unlike musicals, real life often doesn’t have happy endings), and my mother told me later when she came home to a place I would no longer occupy, the house seemed so empty. My father, on the other hand, had a more practical outlook. He said he didn’t notice any difference because I’d only been there lately to eat and sleep. That song about time slipping away also made me think about what it must be like for a parent to watch a child grow into adulthood. I never had that privilege, and as I listened to the song, I mourned that fact.

I also got emotional at intermission when I looked at the ads the performers’ parents had taken out in the program—photographs of their children with expressions of love and congratulations and wishes for success in the future. It made me think of how wonderful it must be to watch a child’s talents develop, but also how parents know a time will come when a child will leave home and step into a future that holds more time ahead for that child and less for those parents. Bittersweet, as life often is, and filled with earned emotion.

So, I admit it. I had a lump in my throat several times. I could say it was because I’m just becoming more sentimental as I age, but the truth is I’ve always been emotional. I’m pretty sure those who knew me when I was young would have called me a sensitive child. I grew up in a working-class part of the country that valued manliness, often to the point of toxicity. We boys weren’t supposed to cry. Really, we weren’t supposed to feel, but I always felt deeply. I was lucky in the respect that my mother, unlike my father, never called attention to what was sometimes my overwrought states. She accepted me for who I was, a boy who felt so deeply he couldn’t help but express his emotions.

I say all this to make this point; a repression of emotion is deadly for writers. We can’t be afraid to feel what our characters feel. The only thing we need to be aware of is the fact that those characters must earn their emotions. What they feel must come organically from the worlds they occupy, the actions they commit, and the consequences they create. We writers need to let our characters get themselves into trouble, giving them agency over their own fates. Otherwise, the sentiment tips over into sentimentality. The emotions seem forced, applied from without, and used for the purpose of manipulating a reader’s response. In short, genuine emotion comes from what a character creates. At the end of James Joyce’s “The Dead,” Gabriel, through his own actions, comes to realize how insubstantial he is—how insubstantial we all are in the forward march of time—and as he watches the snow falling all over Ireland, we mourn with him. That’s sentiment. That’s why I’m thankful my mother let me know, without saying a word, it was all right to be a boy who wasn’t afraid to feel. I only wish she’d lived long enough to see the writer I became, the one she gave permission to express genuine emotion on the page. Like the parents who supported their children in today’s production of Mamma Mia!, I believe she’d be proud.