Do you think he is feeling 100% better? If so and he is just going to go..I would go back to step one..Take him out more. Every hour and after eating and playing, just like when he was new. Also, is the crate only big enough for him to stand and turn around? NO EXTRA ROOM! They often slip backwards, but usually that's about 6 months of age. His seems more like a reaction to being sick and now it can become a habit. He is still very young and he will figure it all out. I am thinking he is still not feeling normal though..