Some parents jokingly call cribs "cages" or "prisons" for their children but it seems that some children take that literally because they actually fear sleeping in their cribs. According to Romper, it's actually one of the most common behavioural issues that parents can face with babies and toddler-aged children during bedtime.
This can be especially frustrating for parents because they know that their children are tired, especially if they have an established nighttime routine set up. So, when little ones revert from being capable of sleeping alone through the night (or at least mostly through the night) to crying out it can be cause for concern.
But never fear! Dr. Lynelle Schneeberg, a clinical psychologist and assistant psychologist at the Yale School of Medicine told Romper that it's important for parents to start thinking about "sleep training" when their child is around 4 to 6 months old.
Dr. Schneeberg also said that this might be the time when the child no longer needs to eat at night for "physiological" reasons but more of a "feeding to sleep" habit reason. She wants parents to clearly understand that younger children (babies) are not necessarily in distress (as in terrified of their crib). Rather, their cries may just be alerting parents to hunger or other important issues.
On the other hand, older children (like toddlers) will start to develop an emotional attachment to their parents' presence at this point, as opposed to babies who purely need their parents to tend to their physical needs. There is a clear difference.
Then there are kids who look for comfort-seeking behaviour due to habit-forming or environmental factors. Dr. Schneeberg says that crib issues usually pop up after 18 months or so after the "sleep onset associations" period.
If the parent consistently rocks them to sleep, the child may have a tough time falling to sleep independently thereafter. They might become afraid to fall asleep "by themselves" in the "scary crib" all alone without their mom or dad to rock them to sleep if the parent is unavailable for some reason.
Dr. Schneeberg recommends training the child to fall asleep on their own in these cases by putting the child in the dry and fed but fully awake and letting them work out how to get from fully awake to fully asleep on their own. She says it's okay to be nearby when your child is learning this on their own. But it's not recommended to pick your child up or even touch them during this time. They need to figure this one out on their own. Trust in them. They've got this! Sweet dreams!