Hi Momma Hens and Rudy Roosters,
This is one of the biggest questions new parents wrestle with, and I don’t think you should just wing it. Let’s use some real psychological science to guide you instead.
What I Learned in the Lab
Back in 1993, I was a research assistant to Dr. Karen Horobin, at the University of California, Davis. We were studying object permanence — an infant’s growing ability to understand that things (and people, including you!) continue to exist even when they’re out of sight. Her work was based on a highly influential Swiss psychologist named Dr. Jean Piaget and his Stage IV theory of cognitive development.
Dr. Horobin designed an ingenious wooden box with three easy-to-open doors; so easy a baby could open them. Hidden inside the box was a movable ramp that let us secretly control whether a ball stayed or rolled behind another door, without the baby seeing it happen.
- We brought babies ranging from 5 to 12 months into the lab and watched what happened when a colorful ball was placed behind one of the doors. At first, the older babies found the ball easily, every time.
- Then, as the experiment progressed, we moved the ball to a different door without them seeing.
- The babies who had developed object permanence got upset and cried when the ball wasn’t where they expected it to be. They knew the ball still existed somewhere — it was unsettling for them not to find it.
Most babies reached this milestone between 9 and 10 months, and all had by 12 months. Some theorists believe babies as young as 4 to 7 months may already grasp it, but our study didn’t confirm that.
What This Means for Your Baby
So, should you let your baby cry it out?
No, not yet, not until they’ve developed object permanence.
Until your baby understands you still exist when you’re not in the room, being left alone to cry doesn’t teach independence. It just leaves them overwhelmed and confused, because as far as they can tell, you’ve vanished.
A Little Grace for You, Too
I know how hard it is to keep waking up every time your baby cries at night. This happens especially often with breastfed babies, since breast milk is about 87-88% water and doesn’t sustain a baby for long stretches. It’s not you doing something wrong — it’s biology. The American Academy of Pediatrics recommends, if you can, exclusive breastfeeding for the first six months, then continuing intermittently alongside solids for up to two years. That’s a lot of nursing — but also a lot of moments to bond with your baby.
So be patient with your baby, and be patient with yourself.
If you need support, pump and store your milk in glass bottles and ask your partner, a relative, or a friend to take one night shift a week so you can get real, uninterrupted sleep. A little help goes a long way — for both of you — during that first precious, exhausting year.