Those of you who share space with a cat and/or dog - a delicate question -
I am very assiduous about cleaning up those little accidents as soon as I see them. I do have one dog that persists in marking things inside the house from time to time.
Now - if i go away for a few hours and come back, I don't smell anything. I did get close to the couch and sniff general dog so i sprayed the couch down with lavender spray and that seemed to take care of it.
My two sisters haven't been in my house for years ( they live out of state). Both are very fastidious (maybe a little OCD). They've both made remarks about how you can always tell a house with animals by the smell.
So my question is - does my house stink and I don't know it?
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I agree, although in our case, it's all about the kitties.
There's a commercial for Lowe's or Home Depot or something that uses that old Crosby, Stills, Nash & Young song "Our House / is a very very very fine house / with two cats in the yard ... " and I always think: "Only two? That's not enough." 
Our house has a certain smell. It's not a bad smell but it is a distinct smell. I notice it more when we've been gone for a few days. My neighbor's house also has a distinct smell in the same way. I like the smell and it's subtle but our houses are old so maybe it's that.
My pets have never been in certain rooms of the house but the rooms they ARE in can certainly smell like dog. My only dog now never pees in the house but his pillows smell like dog and I think the rooms smell doggy until I air them out/freshen them/febreze.
Then again, my house can smell like whatever I've been cooking, too!
Did I mention I have teen boys? 
At any moment you can get a whiff of horse/fart/body spray!
If I were you, I wouldn't give it a second thought.
Just spray some of this around before your sisters arrive.
share my home, furniture,and bed. I vacuum once a week, clean up little messes as needed - hairball barfs usually. No bathroom accidents or marking... And when I am gone for a day or so, I smell nothing but "house" upon my return. Of course it seems everyone's house has a certain smell to it - not a bad odor, just a certain smell of sorts...
if the sisters are scheduled for a visit, I suggest having your carpets professionally cleaned. It freshens the whole house.
Or, better yet, go visit them and take the critters along ! Heh heh heh.. 
Ours is a combo of natural cleaning products, a little dog and cat effluence, some human effluence that we humans can't much smell, and at the moment a delicious curried kale/chickpea/butternut squash soup.
If the Boston events weren't so sad, I'd say it smells like a happy, lucky household filled with a lot of creatures sharing space.
Of course some of us in this little household CLEAN more than others...
I have always had a cat/cats, and, like everybody else in here, I just pretty much accepted that the pet population contributes to the overall "house whiff." Me cooking fish or bacon or a curry probably impacts it more than the cat, but you know that pets are gonna contribute something to it, just like the people do.
To be honest, I dunno how anybody lives in a house that smells only like perfume. I get kinda sneezy when I'm in those places for too long. Plus, you just know that the minute you leave somebody is gonna let out a big fart or go do what people do in the bathroom and then spray another can of air freshener all over the house to cover it up. Can't see how that's healthy at all.
As long as it doesn't smell like there's something (or someone!) dead buried in the crawl space or hanging out in the attic I really don't spend a lot of time worrying about this stuff.
Laura
