I bought a dog house some time ago that can fit both my pits inside comfortably, my pit puppy Neela has no problem with it but my one year old wont go inside it he sniffs the outside and walks away…ive tried putting there food inside it and treats but he stretches his body as far as it can with his back legs sticking out its pretty funny but frustrating..especially since its getting colder at night how can i make him not afraid to go inside..any ideas??