It may have been a bad idea to have children on the Enterprise

Sure, it's dangerous. You're exploring unknown space and all. But you can't prove that with "Lewis and Clark didn't bring a four year old with them!" because, yeah, they did. Well, no. First they brought a pregnant woman, and then once she gave birth they brought an infant. That's not any better for your point. Likewise, the youngest "man" to sail with Columbus was eight. If you're gonna make a freaking historical analogy, do it right or don't do it at all. You can't have a serious conversation about trivial things when people are just gonna be wrong.