We bought a 99 QD last May, and travel with our Bichon. She likes to either sleep with us on the rear dinette/bed, or in her kennel , which fits perfectly under the bed. I think the space under the rear dinette/bed combo makes a nice place for your pet(s), and/or mother-in-law, either one or both.
We also have a Vixen 21TD, and are new to the Rialta. I'd be hard pressed to choose which one to keep if we decide to sell one. Both have wonderful traits, but neither is the "perfect" motor home (yet).
The Vixen has a permanent rear full bed, a nicer bath, a dinette that also makes a bed, a 2 burner stove, a much better fridge that freezes ice cream like a brick on the batteries alone, 13,500 btu ducted a/c mounted in the floor, diesel furnace, a diesel engine / manual 5spd tranny that gets you 30mpg and more power, but it has no built in generator, or electric windows or electric door locks, or airbags, and it's not quite as quiet on the road. However, it does handle much better (4 wheel independent suspension) ,and you can get tires and parts cheaply. Ours has a 2000 watt inverter and golf cart batteries, and we take along a Honda generator. The roof raises to give 6'6" head room, and it's 5'7" inside with it down. It has bigger water/holding tanks. The Vixen fits in a standard garage, being only 6'4 high at the roof with the top down. Really goes good in the snow with the pusher engine. Front/rear weight bias is within 12 pounds the way we use it. However, I'm a bit biased toward the Vixen, having had it since 1998 and know every nut and bolt on it. And besides, it gets a lot of attention everywhere we go. The paint doesn't "black streak" like the Rialta does. Very stout frame. If you jack up the front tire, the rear one comes up with it (if you have a good jack), no body flex.
Now, our Rialta is quieter, with better visibility out the back, a more "open" feel, has a generator, and a bit more storage room perhaps. I like that it has dual airbags, and electric windows/locks, and better headlights, and my wife prefers her captain chair over the Vixen bench seat, and having her own passenger door. But I don't care for the constant setting up for beds/dinette and all the cheap plastic doors, nor do I like the shower. That I will remedy when the weather gets nice. I am going to find a way to install one of the outdoor shower kits into the bathroom so you don't have to put the sink up/down to adjust the water temperature and take a shower. Of course having two showers has an advantage, she can use the outside one, and I doubt if anyone would ever complain about a pretty lady showering outside. I've put well over 150,000 miles on the Vixen, but only 6,000 miles on the Rialta, so we're still learning about it. Both rv's have advantages and disadvantages, depending on what you're looking to do with it. Hope to see ya'z down the road.
p.s., if you want to be left alone when camping, say you've driven a long way and you just want to rest, make yourself a sign that says, "I sell life insurance, visitors welcome!" and hang it outside the door. Nobody will bother you.