looking for kids pony/small horse

Casually looking for a kids pony/ horse, the ideal horse would be 13-14 hands and stockier build, more whoa than go! With absolutely no buck bolt rear kick bite or spook! Looking for a complete unicorn and as safe as a horse can be (yes I understand a horse is still an animal with their own brain) very knowledgeable horse home. Currently riding leadline on a mini but need the next size up as our boy is getting a bit big for his mini! Want one under 18 so we can have many years with the same horse and then will be for our daughter to move up to when she’s older aswell. Looking for one that has many years of riding under them but will mostly be leadlined and ponied off my horse
If you have an unicorn your looking to sell please send me some info on it! Mare preferred but will look at the right gelding also