We are expected to be responsible dog owners, pick up, train them and keep them under control/well cared for, why don't parents teach their kids not to run screaming around dogs or run over to them and start trying to tug their tails/ride on them?
Also, to expect that kids should not be walking dogs on their own or at a significant distance from their parents with a dog that is:
A) Heavier than them
B) Has serious behaviour issues
C) A & B combined means said child has no control over dog.