I don't lock up whatever weapon I have out for defense. That's not where it needs to be. It needs to be with me. It's on me most all the time less I'm at my desk for a while then it's on my desk. I put on my night stand when I lay down. I don't have kids around the house much anymore.
If one was to have kids in the house it's your job as a parent to teach children to never touch a firearm. I taught my kids early and often that guns are not toys and they are very dangerous for kids to handle without proper supervision. My kids are grown and still would never touch a firearm in my house unless it is me that is handing it to them.