Yes, there's a difference between a dog launching itself at a child for no obvious reason, and the situation Seasider is dealing with here. The lovely spaniel we rescued bit a visiting child on the face despite two adults being present, and the child not approaching the dog. It caused an injury that required stitches (there was no permanent scar). We had gone to great lengths to check out the dog, who had been through a period of rehabilitation with the the original breeder - he had taken taken her back from the owners who wanted to show her, but then neglected her when their own litter produced the puppies they preferred. The vet said, when looking at her background, he thought the visiting child would have been seen as a usurper taking the family's affections from her, so she leapt at the child. As we had four young children at home, and could not trust the poor dog not to do it again with any child, she was put down. We complained to the Kennel Club about the owner who neglected her, with the help of the breeder who had taken her back. A tragic situation all round, but we would take the same decision again in such circumstances - hard to do when you are a dog lover.
I hope you have no more problems, Seasider. It's good to hear that your efforts to make things safe are appreciated.