I remember being concerned about the same thing with my oldest. She was a REALLY sleepy baby. I had her on a 3-4 hour feeding schedule, and she LOVED it. She would sleep all night and then wake and sleep for a few more hours, and then have 2 solid naps during the day and more if we put her in the car or stroller! I was constantly told by my inlaws to wake her up and not to let her sleep so much and how it isn't healthy. I trusted my instincts and just kept to the schedule (even if I had to wake her for her feedings) and she is now going to be 9 and is a GREAT sleeper. She is also very intelligent, which they have tied to good sleeping habits. Don't worry too much about it, and just stick to your planned day. Babies don't really need as much awake time as you'd think, since their brains are doing a lot of learning and growing and that is exhausting to the little bugs. As long as they get the appropriately timed feedings and SOME awake time, they are good to go. And this is a totally random thought, but I believe I read that preemies sleep MORE then usual, making up for the time lost in the womb, so if they were early at all, they may be a factor. My daughter was 2 weeks early, but I don't know if this is just hearsay or not. Good luck and congratulations on your little babies!