We have a 6 month old Texas Heeler for 3 months now. He does great in the crate. Fantastic. He will go to the door to go out - most of the time. But he goes out to pee every 30-40 minutes! And if I don't know he's there (he doesn't bark), he'll pee right there. Or walk off and pee wherever. He can last for hours in the crate, even all night. But less than an hour outside the crate. What am I missing?