I hope we don't have to do formal sleep training, but we'll see how it goes. (rookiemoms.com)
But as desperate as you may be for some solid shut - eye, your baby won't be ready for formal sleep training until she's at least 4 months old. (babycenter.com)
Sleep Shaping with your newborn (0 - 3 months)-- how to create healthy sleep habits that will lay a great foundation for future formal sleep training (anytimesleepconsulting.com)