How do you explain to your children (toddlers) when the violence in adults and even within the family?

When we raise children and when they have an understanding of emotions, they also understand which emotion is happy and which isn't. When the kid starts responding as early as 3 or 4 months and giggles when ever you make him laugh and makes a face or cries if he sees someone with a sullen face or fearful expression... it shows that kids are born with a programmed brain where they know that violence is bad. As they grow up, they only want an assertion from his caretakers whom he trusts the most that violence is not good. And when he gets that, he knows and grows up to be a human being who would not like violence or loud behaviour in his life.