Should I keep my (wife's) dog away from my new baby?

[DrewDevil]

My wife and I have a 3-month-old son who is starting to turn over, play on the floor, etc. He will soon be crawling and teething (which means he will try to put everything he touches into this mouth).

We have a 6-year-old little dog who weighs about 10 pounds and is an inside dog for the most part. The dog sleeps in our bed and pretty much goes wherever she wants. This was my wife's dog originally and she is very fond of it... I think the dog is fine but I'm not terribly attached to her.

The dog, like all dogs, is pretty filthy in my estimation. If left alone in the apartment, she will pee or crap on the floor. She throws up on the carpet from time to time. After being walked, she likes to come back inside and either lick her butthole for a while or drag her ass along the carpet.

I am not real excited about this squirrel dog licking my son's face, spreading her fecal matter all over our floors, etc. My wife doesn't seem to think it's much of a problem and "has read" that being around the dog will actually help my son "build up a resistance" to germs.

I don't know if I should just let this go and not worry about it, throw a huge fit and demand the dog be quarantined away from him, or somewhere in the middle.
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