I don't know if I'd lie to my kids about this subject directly (I don't have any so this is hypothetical), but I also don't know how I'd talk to them about using violence. I wouldn't expect a kid to understand the difference between proactive use of violence, disproportionate use of violence, and an appropriate use of violence. And if we're talking about a boy, I don't even know how you begin to talk about gendered violence. Realistically, you just tell them don't hit anyone unless they've hurt you and are gonna keep hurting you, and if they're a boy you teach them never to lay a finger on a girl for any reason? But both of those are "lies."

That's kind of a heavy example, but it's the first thing that came to mind. You'd probably find similar examples with lots of topics that kids may ask about though, like if they ask what a bad word means and you don't want to spend a lot of time explaining things they'll have lots more questions about? I don't know, maybe that's unhealthy too, but realistically you'll always end up telling your kids some things that aren't 100% true just for practical purposes.