WB still hasn't got the hang of going to the door to let me know he wants out. i can take him out for a wee, tell him "do pee pee" and he does then a maybe 10 minutes later he will go again in the house but shows no signs of wanting out. he could just be running across the living room then he stops and pees. am wondering if i train him with a bell at the door would it help him? and where can i get a bell?