What is the ruling on attaching children with a rope in the form of a harness to walk them, and is this considered imitation of tying dogs when there is an urgent necessity, such as the child being very active and there is a fear of him running into the street?

There is no harm in tying a child with a rope to protect them from dangers, as long as their body is not harmed. It is imperative to ensure that this tying does not lead to a reprehensible meaning, such as resembling dogs. Therefore, the child should be tied from a place other than the neck, because the neck is more likely to harm the child, and because the Prophet, peace and blessings be upon him, forbade resembling dogs, and because resembling animals is generally forbidden.