Developmental milestones — rolling over, babbling, transitioning to solid food, walking — are a huge source of anxiety for parents, who grow concerned when their kid fails to keep up with what turns out to be a largely artificial calendar. Every parent wants to know that their kid is developing in a healthy way. Unfortunately, baby milestones are neither an effective way to diagnose cognitive growth nor a particularly helpful idea to obsess over.
The reality, as documented by scientists and experts the world over, is that kids arrive at infant milestones and baby development milestones at different times and in different orders. That’s why the word “milestone,” which connotes linear progress, is flawed to begin with and also why it’s so sticky. People love the idea of a path. It has been that way since our ape ancestors came down from the trees. But these waypoints to health are largely a myth and when parents talk about them, they tend to get lodged on precisely five other myths along the way.
Baby Milestones are Broad Targets
Milestones, as they are related to navigation, are fixed points along a path that gives a traveler an indication of where they are and the distance they’ve gone. The term could not be any less suited to developmental milestones. That’s because how and when a kid develops an ability, be it physical or cognitive, depends on a huge number of factors that don’t fit into a linear path that everyone can be measured against.
That’s why many developmental milestones are given age ranges that can cover multiple months. These ranges represent the average age in which a typical child will develop certain abilities.
“For instance, walking is a big one,” says American Academy of Pediatrics Fellow and Developmental Pediatrician Eboni Hollier. “Probably about half of the kids will start walking by the time they’re 12 months of age. But nearly all of them will by 16 months old. In my mind, anything between 9 months and 16 months is okay for walking.”
But that does not mean that children outside of the average are somehow advanced or deficient. In fact, by the time children are in grade school, most are operating on the same developmental level regardless of whether or not they’ve developed some abilities more quickly or more slowly than their peers.
Baby Milestones Occur Along Different Developmental Paths
“We have to understand that development occurs in many streams,” says Hollier. “For example, walking is gross motor. Picking up something like a Cheerio is fine motor.” Add to these the cognitive streams that lead to communication and it’s easy to see that the linear development many parents expect is a failed model. “The way development goes sometimes you might do some in one area and less in another,” Hollier adds.
She notes the better way to mark development is by recognizing a child’s natural developmental rhythm, or pattern. That could be difficult considering many baby book guides or developmental pamphlets don’t give parents this option, but Hollier says that pediatricians are adept at teasing out developmental patterns to help parents understand where their child is at. “Understanding the pattern that your child has is more important than any one milestone or moment in time.”
Baby Milestones are Reached at Their Own Pace
The baby product market is lousy with various flashcards, toys, and tools meant to help a kid reach both cognitive and physical developmental milestones. But parents should understand that these accouterments don’t hold some magic key to make their kids stranger, faster, or smarter any sooner. That’s largely dependent on the way their nervous system is developing.
“The way the neurological and muscular system develops is from the top of the head to the toes,” Hollier notes. “Then it develops from the midline out to the fingertips.” This is why babies gain head control first, followed by control of their trunk to sit up, pull up and finally walk.
Adding special toys or tools can’t really speed up that process. And all of the things that the tools do can be accomplished by parental attention, touch, and play. That said, a lack of opportunities to work on growing skills can put a child behind. But there are no special tools or objects required to keep development on track.
Taking Longer to Hit Milestones Doesn’t Always Indicate a Problem
Kids develop at their own pace. Yes, enough of them develop at a similar pace that scientists can create large targets for when they should be able to do certain key tasks, but it’s all relative. So parents who worry that their child may be experiencing some kind of developmental disability because their child is “slow” to roll over or sit-up can take a breath.
“Motor skills don’t correlate as well with cognitive development or intelligence than say, speech and language skills,” says Hollier. She notes that if parents are truly worried they should speak to a pediatrician who familiar with their child’s pattern of development for peace of mind.
It’s also important to note that are many factors that could slow development aside from a disability. Children who are born prematurely will develop at a speed commensurate to how much earlier they were born. Expect a child who arrived a month early, for instance, to reach their milestones a month late.
Temperament also has a great deal to do with milestone achievement. An outgoing, adventurous, risk-taking child may be quicker to crawl in order to explore and discover. On the other hand, a cautious child might rather stay in one place, or stay by their parent rather than strike out into the world.
Siblings May Reach Developmental Milestones at Different Paces
Finally, just as parents shouldn’t compare their kid’s development to others in their cohort, they should be cautious in comparing siblings. Just because children share a genetic root, does not mean that they will share the same developmental progress.
“Parents will come in and say, ‘Well my first kiddo walked at 8 months. And this one is 13 months, they must be delayed,’” says Hollier. “Well maybe the other one was a little bit early and this one is right on time.”