My 6 yr old min pin is pooping in the house while I'm gone during the day. He has a dog door so he could go out any time he likes. He has done this occasionally in the past but it has increased recently. We've had him 2 years, but he was a stray from the pound so we know nothing about his past life or training. He seems fine left in his crate, but is 8 hours too long (in addition to hours at night?) Not sure what to do with him while I'm at work.

