So your baby is managing to sleep a solid 10 - 12 hours at a time. That's great! Or at least it would be, if it was happening at night.
This is actually a very common scenario with parents of infants, where their little one seems to have their days and nights mixed up. They sleep almost all day long, then wake up in the evening and stay awake throughout the night.
So is it possible for your little one to actually establish a nocturnal sleep pattern, and if so, what do you do to remedy the situation?