What companions have YOU SEEN work well with horses?

The great thing about donkeys is that they teach your horse manners. If you tie the horse up to the donkey the horse will no longer have any bad habits on the ground, however the horse will hate the donkey. I have a friend that has a donkey that lives with her horses and it works great for her. My old horse lives with a goat at his new home and they have never had any problems (he's the kind that gets wayy too attached to anything that moves). I don't think sheep are the best, and llamas scare me too. I'd personally go with either a donkey or a goat. I've always heard great things about them. Would a cow work? It might eat too much but that's what my grandma put her colts out with in order to wean them. I definitely wouldn't get a dog because almost everyone I know has had a dog macred by a horse because the dog startled the horse either in the field or in the stall. I agree with an earlier comment that said horses are the best. I would think that any animal would bond with your horse, though, so just take whatever you can find. I bet a lot of rescues have some donkeys and maybe goats you can adopt.