Prototype: Kids Protector for Dog Leash

My one and half year old daughter love to keep the Retractable dog leash in hand when we walk our dog, one 3 years old poodle. But this will be dangerous for her when dog rush out suddenly.
The protector can control the leash to stop the dog and another side is free to drag and retract for my daughter at same time.
This is one prototype and I will enhance the stop power after trying.