If your kid is wild about animals, let her woof it up with a pet party! Send out animal-themed invites to her friends and their pets, then wait for the fun and fur to fly. If your little animal lover is inviting her entire class, you can set stricter regulations on the beasts of honor, such as dogs only, and plan to have the party in a large, animal-friendly environment like a dog park or, if you've got the space, your own backyard.
Is your child is inviting a smaller, more manageable group? In that case, you've got some wiggle room to invite anything that mews, barks or blows bubbles. Allow creatures of all types to attend, from fish and ferrets to felines. Section off an area of your home, but beware of guests with long-standing instinctual feuds. You'd be surprised how much chaos a few fleeing cats and one determined dog can cause, so make sure all furry party attendees undergo a temperament test before they're admitted. Mandating that everyone's up to date with vaccinations isn't a bad idea, either, and be sure all parents understand the party's theme so children with pet allergies will know to decline the invite.