M.M.
My son, Joshua is 5 and does the same thing. He is getting alot better, he does actually sleep in his own bed quite-a-bit, but still comes in my room once in a while. I just kept telling him he was a big boy now, and he sleeps in his own bed. Your son will eventually grow out of it i think, like Joshua is. I don't know about the sippy cup. I can't remember what i did for Joshua, because he liked his cup too!! Maybe convert to the cups with the straws, and get away from the sippy ones. Good luck!!!