My guess is they pee because there is less of it...and they think that they won't get caught.
Also, I do think that brains has something to do with it.
When Izze used to have accidents---it was because she was nervous...and now that she is calm--we don't have as much (hasn't had one this month). Keep in mind that we've only "owned"her since July and she came to us with lots of emotional issues.
Molly--my poodle---is my smartest dog and she would not think of peeing in the house. She knows that it is not acceptable.
Chachi-- he is very well trained and is the same way.
Suzie---my youngest baby poodle and she is dumb as a box of rocks. Very stupid. I mean... she stares blankly at me when I'm trying to teach her something. So the best that I can do is take her out often...I don't think that she'll ever be potty trained.... she usually has pooing problems. She rarely pees in the house. She's beautiful, but really dumb...I've been trying to teach her tricks and she doesn't seem to get it... I love her though
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Chrissy, Izze (Yorkshire Terrier),Molly & Suzie (Toy Poodles), Chachi (Chihuahua)