The question we're asked most often at Let Mommy Sleep is "When will my baby sleep through the night"? In our American culture where many parents have little support and don't have the opportunity to sleep when the baby sleeps because we have to go, go, go this is a perfectly reasonable question. So when your pediatrician agrees that baby is physically and developmentally able to sleep 6-8, and eventually 10-12 hours uninterrupted there are 2 answers:
1) Simply follow baby's lead and don't worry about when s/he sleeps through the night. The End.