Once again this tragedy rears its head, and once again there is the usual knee-jerk reactions.
Anyone owning a dog should accept one simple fact. Dogs are pack animals - from the smallest to the largest, that is a genetic fact.
Because packs have a pecking order, any dog needs to be advised of its position within the order, and discouraged from its natural tenedency to move up the order when it feels an opportunity presents itself.
Sadly, in a family environment, the parents will always be seen by the dog as 'senior' members, providing food and disciplione for all the pack, but children are seen as intermediate pack members, and therefore can be seen as worth taking on with a view to assuming their position.
This simple fact means that any dog, of any size, and any temprement, has the potential to attack a child in the household where it lives.
Failure to assimilate that fact, or to ignore it because 'our Poochy would never hurt a fly' is foolish and dangerous.
Proper thought should therefore be given to the size and potential damage your chosen breed of dog could do if circumstances led it to try to move up the pack at any time - bearing in mind that this is likely to take the form or a physical attack without any prior warning.
That leads to a simple conclusion - if you have small children, don't have a big dog.