Ace, the Very Important Pig by Dick King-Smith.
Ace is a descendant of that famous sheep-herding pig, Babe, we all know and love. Unlike the other farmyard animals, Ace can understand people talk. This leads to just the kind of comic intrigue we enjoy. Lots of fun character-voice potential, too. Her Lowness, Megan the Corgi gets my best Queen Victoria impression, naturally. (Er, that is, Queen Victoria as portrayed in the Horrible Histories English Monarchs song.)