Care and Feeding is Slate’s parenting advice column. Have a question for Care and Feeding? Submit it here.

Dear Care and Feeding, 

I have a 7-year-old son, “Chase” and an almost-3-year-old daughter, “Cheyenne.” My son has “solved” one problem I was having with his sister, while creating another.

Our family lives on a lake with a fenced-off dock. Cheyenne is constantly trying to go down there because she loves feeding the ducks that live on it, which means we have to constantly be on our toes with keeping the fences gates locked at all times. Last week, I asked her if she wanted to go feed the ducks some expired bread. She shouted “NO!” and ran to her room. I was surprised and asked Chase if he knew why his sister seemed so scared of going down to the dock all of a sudden. It turns out that he did. In fact, something he did is the reason why she’s so scared.

Chase said he came up with a way to keep Cheyenne from trying to go down to the dock by herself so she would stay safe. Apparently, he told her that a monster lives in the lake that likes to eat kids who are under 7 years old.

Now Cheyenne doesn’t even want to go out into the backyard. If that weren’t bad enough, now she’s also afraid of the dark. She won’t sleep without a nightlight and needs me or my husband to stay with her until she falls asleep. I had my son tell her he made the whole thing up and there’s no monster, but she doesn’t believe it. Now what?

—Thanks a Lot!

Dear Loch Ness Mom,

Once an idea gets in their heads, it can be extremely difficult for kids to let it go, at least on your preferred timeline. One day she may wake up and completely forget about the monster by the lake. In the meantime you need to emphasize that monsters don’t exist, and are just like the other things that don’t exist (like unicorns and healthy potato chips).

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Start with some unicorn books. When my kids were younger, they liked The Princess in Black. That series features lots of things that don’t exist. Talk about the difference between the real world and make believe. After that, escalate into monster territory, with books like There’s a Monster in My Closet, I Need My Monster, and The Monster at the End of This Book (in which an extremely lovable and furry Grover narrates, and—spoiler—is also the monster the end of the story). If you think she can handle it, try watching Monsters, Inc. All the while, make sure to emphasize that monsters are not real and even if they were, they’d apparently just be loveably misunderstood drooly creatures. Remember that the Sesame Street crew has many monsters, too!

This situation is also a great lesson for your son on how lies can have unintended consequences. Chase needs to take responsibility for the result of his lie. Have him take part in helping to build up his sister’s confidence. Have him read the books aloud and find new ones for her at the library!

Allison Price Read More

If she can handle some basic logical thinking (not necessarily the forté of a 3 year-old), try to find a way to prove to her that there is no Lake Monster. The ducks she loves aren’t afraid of a monster and they’re still at the lake, maybe she can be more like a duck! Maybe she can be an imaginary protector of the ducks against the imaginary monster (with supervision, of course). Have Chase explain why he lied to her. He was trying to protect her from the water because it’s dangerous. Though they’ll likely fall on deaf ears, appeals to reason never hurt.

Honestly, having water nearby a three year old gives me anxiety. Easing her fears will take time, and on the bright side: it does sound like she’s going to stay away from the dock.

—Greg

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