Since people have been mentioning they are newish parents, and worried about kids getting into their guns, let me just tell you what I've been doing. I have an almost 1 year old (will be 1 in April) and an almost 4 year old (will be 4 in May). My guns are always in one of two places...either on/with me, or in the safe. If I am doing something with my gun (dry fire, cleaning, etc) and something else takes my attention, the gun either goes right into my holster on my body, or back in the safe. Carrying Condition 3 does not make the gun any safer for kids, if you follow these simple rules.
My 4 year old knows where the safe is, but knows not to touch it. She also knows that if she wants to see a gun, all she has to do is ask. Even though she is very curious about many things, she see guns all the time, and she just isn't that curious about them.
I would never consider a gun in Condition 3 to be safe around a kid. Rule 1 makes this clear, "All guns are loaded, always." I know that everyone's situation is different, so this won't always work for everyone, but it's my belief that a combination of restricted access (except around Daddy), and education (Eddie Eagle's video is great, my daughter actually asks to watch it on occasion) will be your best defense against catastrophe with kids. Hoping that a gun at Condition 3 will keep them safe is dubious, at best.