The scene never states just what upset Big Bird, and this is not unusual, according to Daniel Anderson, a developmental psychologist who has consulted on many kids’ TV shows, including Mister Rogers’ Neighborhood, Blues Clues, and Sesame Street, though he was not involved in creating these resources. Writers often choose not to show the inciting event to avoid upsetting young viewers. Also, “you almost never see characters crying on a kids’ program,” he told me, “even though it would be far more realistic and gripping to the audience, but if you do that then the kids can get very upset.” And it’s true that in all the Sesame Street videos on trauma I watched in researching this story, I never saw a Muppet cry, though they hang their heads and speak sadly.

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For each topic, the Sesame writers boil down what they’ve learned from research and heard from advisers into bite-sized phrases such as “big feelings.” Avoiding overexplaining, Thomas says, is also key. For foster care, the takeaway phrases the writers settled on were: “You’re safe, you’re strong, you belong”—which the Muppets sing in song form in one video—and “for-now parents” as a kid-friendly synonym for “foster parents.”

Adriana Molina, an adoptive mom of two children—a daughter, 3, who was formerly in foster care and a son, 10, who is her wife’s relative—has learned to pay attention to the transitions in her kids’ lives. “When [our son] came into our lives, we thought he was going to come for a visit, and he ended up staying,” Molina, the director of Project ABC, a program in Los Angeles that works with young kids and their families, told me. “We didn’t know to give him as many of the words for This is what’s happening, or This is what’s changing. Whereas with [our daughter], she’d only been in one foster home her entire little life. We were able to ease into that process and do some visits in her space. Slowing things down was a very concrete learning” experience, she said.

Molina was an adviser for Sesame’s foster-care resources, bringing both her personal and professional experience to the process. “‘For-now parents’ is a lovely, neutral place to be,” she said. “The language of being in foster care is it’s where you are now; it doesn’t necessarily mean it’s where you will always be.”

But that concept of temporariness is often hard for young kids to grasp, according to Anderson. “Preschoolers have such a limited time frame and sense of past and future,” he said. “And something like homelessness, even if it’s temporary, it might be temporary in terms of months, which would seem permanent to a child. That’s a very difficult thing to deal with.” Ideally, he suggests keeping conversations with very young children in the realm of yesterday, today, and tomorrow. The idea that things are a certain way “for now” and might be different in the future is “not a real reassuring kind of notion because preschool kids really crave stability and security.” But, he says, “it’s honest,” and for kids going through something such as homelessness or foster care, "I guess that’s probably as good as you can do.”