Kids are curious
This is the key to most of life. This is how kids learn. As a parent, it is my job to satisfy my kids' curiosity in an appropriate, safe and respectful manner. My kids are curious about my guns. How they work, how to take them apart and how to clean them. They are also curious about the game I hunt. I tried, once, to "protect" them from the goriness of field dressing a deer. When they arrived, the first thing (only thing) they REALLY wanted to see was the gut pile. Now, field dressing a deer, cleaning a squirrel, whatever, is a biology lesson. It's not pleasant and glamorous, but they know their internal organs AND where the food comes from.
So, rather than "protect" your kids by hiding the guns and never exposing them, satisfy their curiosity AND educate them on safety and respect. Then, should they ever encounter an unsecured firearm, they will know what to do AND the curiosity will be far less - because they'll know already.