Madeleine Deliee has written about education, parenting and geek culture for The Washington Post, Playboy, Pacific Standard, Woman's Day and Ozy. Follow her on Twitter at @MMDeliee. The opinions expressed in this commentary are those of the author; view more opinion articles on CNN.

(CNN) I became a foster parent thinking I knew everything about what I was getting into. Foster family experience? Check -- my sister was adopted from foster care. Child-rearing experience? Check -- two bio kids, plus years as a high school teacher of classroom interaction with my students. On top of that, I had hours of training and a gigantic binder provided by the placement organization. But what I didn't know could have filled volumes, and watching the new film "Shazam!" recently brought all of that back.

Madeleine Deliee

In the movie, Billy Batson, the soon-to-be superhero, is also a foster kid. His latest placement is a group home that his roommate/sidekick Freddy Freeman warns him "gets pretty 'Game of Thrones' " -- before admitting that it's not really bad. In fact, the place looks warm and welcoming, if a bit worn around the edges -- like the house in "It's a Wonderful Life." You almost expect the finial to come off the staircase post in Billy's hand.

Say "foster care" to most people and they think of two tropes: the saint or the villain. When we became foster parents, others blessed my husband and I so many times for our heroic generosity, we started to wonder how we were getting mixed up with Mother Teresa. Conversely, the typical image in literature and entertainment is the parent with no intention of parenting -- negligent at best, abusive at worst, and often depicted as "in it for the money." The unloving woman who housed Anne Shirley and made her care for multiple sets of twins before she wound up at Green Gables; the people who locked Temperance Brennan (played by Emily Deschanel on "Bones") in a chest for breaking a dish -- these are examples of the long-standing mainstays.

Despite the occasional glimmer of light in recent offerings such as "The Fosters" and last year's "Instant Family," I've come to expect this equally unfair duality in most representations of foster families. Therefore, I was unprepared for the portrayal of fostering in "Shazam!"

Watching the movie, I realized I was holding my breath, waiting to see whether this would be the sinner or saint version of foster parenting. Much to my relief, it was neither. Instead, the struggles of fostering were not only portrayed accurately, but they were also depicted with compassion.

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