This is a question most NICU parents ask themselves, but may not actually ask their nurse.... And here's my thought:
I truly believe that babies know the spirit of the people around them. We've got more than 120 nurses in our unit alone, and although there are 120 different personalities with 120 different levels of interpersonal skills, one fact remains: We love our babies. The Good Lord knows moms and dads can't be with them all the time in the hospital; and I wholeheartedly believe that He takes care of that little minor detail. For even the least of His creatures of the field He provides for..... and I fully believe that babies know they are in the presence of a loving soul (be it their nurses, the doctors, or even the security guards that "ooh and ahh" over how cute the babies are during their nightly rounds....) it doesn't matter what loving spirit they are in the presence of, I believe they can feel it. Someone (much more powerful than us) will make sure our babies feel love and acceptance.... even when their parents are unable to be at their bedside.
Matthew 10:29-31 (New International Version)
29 Are not two sparrows sold for a penny? Yet not one of them will fall to the ground apart from the will of your Father. 30 And even the very hairs of your head are all numbered. 31 So don't be afraid; you are worth more than many sparrows.