Sometimes inspiration just hits you over the head...
Check out this video of a boy and his pony. The pony has so much personality (and he's SO NAUGHTY!) that he practically begs to have a story written about him.
Bearing in mind that no one ever got hurt, and that this pony was much-beloved, watch and enjoy :) (My favorite part is when the pony lies down and rolls!) Then if you're inspired, write the first sentence of a pony story in the comments!
And lest you think he was always this bad, he does have a good side :) There are related videos about the pony being good and the bond between the boy and the pony. They are quite long, so I didn't include them, but if you love horses, please watch them. Very sweet :)