M.N.
I can't remember what my kids did at 6 months, but I always go back to "Healthy Sleep Habits, Happy Child," a book by Marc Weissbluth. I will have to go find the book and look up that age, but if you have time to swing by Barnes & Noble or Books-a-million, they will have it and you can flip through it. He has so much experience and such a relaxed, real, personality and philosophy...but sleep is key and getting a routine makes all the difference in your child's disposition!! Let me know if you want me to just look up anything for you--
M.