Some dog owners naively assume a natural affectionate relationship between children and dogs and we hope that what you have suggested is true in most cases. People with both children and a dog may indicate that the dog will be a long-term companion to the child as it grows and even protect the child against outside dangers. Unfortunately, there is evidence that strongly supports the view that there is a greater likelihood that a dog will bite a child in the family than protect it from an external threat. Of the dog bites to children that will occur each year, most will involve the family dog or a dog that belongs to someone the family knows. In other words, the problem is mostly with owned dogs, not strays. Additionally, as one writer stated, "Children are lead into a false sense of security by stuffed toys, television movies, and cartoons that give animals human characteristics. Kids and dogs can be a natural twosome, but when dogs bite, children pay a disproportionate price." (1) This may be especially true with a family-owned dog or the dog of a friend or neighbor.
1. Rieck, D. 1997. Dog bite prevention from animal control's perspective. JAVMA, 210: 1145-1146