In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Q: Sentence1: David watched an episode on TV about a horse that paints. Sentence2: He thought surely his smart horses could do this, too. Sentence3: At the art store, he bought large canvases, brushes, and acrylics. Sentence4: He taught the horse to hold the brush in his mouth by the handle. Sentence5: David hung his horses masterpieces all over the barn.
A:
David's horses, Horse, David