All children don't have the knowledge, experience, reaction time or common sense to ride a horse appropriately. Give them stronger artificial aids is a recipe for disaster.
There was a 5 year old in a parade a couple years ago somewhere in America. Her parents put her in a parade alone, which was against parade rules in the first place. One of the horse drawn wagons lost control and her horse reared and dumped her. She was crushed under the wagon and died on the scene.
Typical example of bad parenting and the lack of reinforcing parade safety rules. I didnt follow the case all the way through, but I do believe they were going after the wagon owners for fault. In my opinion, the parents and parade officials were at fault.
Bad parenting is rampant when it comes to horses. Everyone wants to show their child off to prove they have the coolest little kid or calmest stallion. My 3 year old has only been on the back of a horse a handful of times, and all the while she had an adult on the ground holding her. I won't be injuring or losing her because I ignored common sense.