We travel with not less than 4 dogs...all of which simply love to travel...(thank the Ghods for that!). This gets interesting in a 22-footer with three humans aboard as well.
One is a Tibetan Terrier (Teddy)--like a Shi-tszu on steroids. He weighs about 25 pounds, is a big goofy ball of fluff, and loves to explore and sniff-test campgrounds and their occupants. He's never met anyone he did not like to get petted by...
His best buddies are a pair of Pomeranian/chihuahua mix brothers from the same litter--one brown and tan and the other mostly black with a few white fur accents on chest and toes. They are hinged together and follow Teddy like little furry shadows. Vader and Chewbacca are inseperable, and usually too afraid of strangeness to stray far from the trailer.
Chocolate is our semi-retired old lady chihuahua mix, not related to the boys. She is fairly laid back and enjoying her sunset years as best she can. She does 'mother' the pups occasionally, and tends to play rough puppy style when noone is watching.
All these beasties are rescues, get along well, and are carefully kept on leashes outdoors, sleep in the back seat of the TV on the road, relax in the Airstream at night, and generally enjoy being on the road--as long as they are with us and fed on time, they are content.
We let them stay in their crates in the trailer when we are eating in a restaurant on the road--assuming the weather is cool enough for Fantastic Fans to keep them cool. If not, it's Dad runs into Cracker Barrel for takeout while rest of family walks doggies behind the place. And yes, we pick up after them--always.
They are our furry family, and we rarely board them--last time the dog boarding cost more than the family vacation stay at Disneyworld...sigh. The greeting when we came to pick them up was massive...next time we're going to stay at Fort Wilderness or equal.
Can't fathom having a cat that would be this much fun on a trip, however. We're not cat folk.