My oldest son will be 14 in a little over a week. We got him a new cell phone for his birthday.

He was so embarrassed by the “Flintstones” aesthetic of his old flip phone that he often pretended not to have a phone at all. But his 11-year-old brother was glad to inherit it.

Yes, the boys have entered cyberspace. That is, they have Facebook accounts and they text their friends. Our daughter, 8, is still content with Club Penguin and GirlsGoGames—for now.

I am ambivalent about the kids being on Facebook. For one thing, they’re not old enough to use the social network according to its stated terms and conditions, so we lied about their years of birth to sign them up.

For another thing, what the kids do out there online could follow them forever.

When the kids first got on Facebook, my main concern about their posts was their spelling and punctuation, not their use of profanity and multiple demonstrations of poor taste. Why shouldn’t they feel free to express themselves?

But my sister works around college students, which I don’t. So even though I don’t agree with all her views, I took it seriously when she called the boys out and wrote:

“I work with college students for a living and I have seen people not get jobs, lose jobs, get kicked out of things, lose friends and even commit crimes or have crimes committed against them—and FB and emails were very involved. Once you put stuff out there into cyber space it never goes away ... even if you think you deleted it or blocked it, it's still there.”

That’s a scary thought, and I took it to heart. I started occasionally censoring the boys’ posts, which we all hate. I also remind them daily, “Do NOT take pictures of your junk. Ever. Period.”

But the thing I like about them being on Facebook is how much it’s enriched their face-to-face social lives.

When I was a kid of 11, if I was bored, I took off and knocked on friends’ doors—over a range of about two miles from home, with no supervision. I stopped at the convenience store or the video arcade. I looked at trashy novels and magazines in the drug store.

There hasn’t been any real uptick in child abductions or violent crimes against kids committed by strangers since 1979. But it’s no longer socially acceptable to let your tweens roam the earth.

My kids don’t have the same freedom or spontaneous social interaction that I had. But being on Facebook gives them some of it, at least in a virtual sense. They can hang out there without being scheduled or overtly, constantly supervised.

Kids need that space. The challenge for us as parents is making sure we teach them what they need to stay safe out there, whether it’s bicycle safety or the fact that the teen girl who wants to be your friend on the Internet may be a sweaty middle-aged man who does not have your best interests at heart.