Depends on how old the morkie is. If it's too old 8+ years you don't want to go through another painful experience so soon. If it's under that age definitely the morkie for sure. You'll be saving the dog and also like you said, it's already house trained and socialized.... Just as I'm finishing typing this my 7 months old morkie took a poop under the bed..serious. Geeezus... See what I mean?