It should be in your view at all times. Even if you don't own a gun you should check with other parents where your children frequent, who might own a gun, to be sure safety precautions are followed. Parents should discuss firearms safety with their children and tell them what to do if they encounter a firearm. The head of the house must teach safe gun handling to all family members. Without proper education, preventive measures are nearly useless.
Children are never too young to begin the lessons of safety.
Teaching can begin long before the child is old enough to understand detailed instruction. Start by setting a proper and consistent example. If parents treat guns with care and respect, children will likely follow their lead. The second stage is more difficult, but well worth the effort. It involves convincing the child that firearms are not toys.