70 Interesting Facts about Child Development

By Karin Lehnardt, Senior Writer

Published March 10, 2017Updated September 30, 2024

Child development refers to the changes that occur as a child grows and develops in relation to being physically healthy, mentally alert, and emotionally and socially healthy._[8]
Some scientists believe that infants’ rapid brain growth mirror the changes that have been shaped over eons of evolution._[5]
A baby is cute according to what scientists have labeled as a “baby schema.” This schema is a set of features that include a rounded head, large eyes, protruding cheeks, a big forehead, round body, and soft surfaces._[5]
Researchers note that a baby’s brain is like a lantern: it is vaguely aware of everything. An adult’s brain, on the other hand, is more like a flashlight, consciously focused on specific things but ignoring background. Scientists suggest that creative people have retained some ability to think like an infant._[1]
Scientists believe that humans are evolutionarily programmed to find babies cute to ensure that babies are cared for, even through restless nights and bouts of colic._[5]

A baby's cry triggers emotional responses in the human brain unlike any other sound

Evolutionary biologists suggest that newborns are born with an annoying cry so that parents won’t get too emotionally attached while the baby still has a high chance of dying. Additionally, crying gets the attention a baby needs to survive._[2]
Parents typically respond to 50%–60% of a baby’s vocalization. However, language development could be sped up if parents responded to a baby’s vocalization 80% of the time. Beyond that, learning declines._[5]
Researchers note that babies may cry with the intonations of their mother tongue._[5]
Trauma or exposure to toxins during the prenatal period can impact later childhood development. Some dangers include prenatal exposure to drugs, toxins, and disease._[8]
Childhood development depends on the interaction between genes and environmental variables. For example, a child may have the genes to grow tall, but if it doesn’t have the proper nutrition, it may never achieve full height._[8]
The development of language occurs in four stages: 1) babbling stage, 2) single-word stage, 3) two-word stage, and 4) multi-word stage._[5]
Researchers suggest that the majority of parents fall within one of four different parenting styles: 1) authoritarian, 2) authoritative (which is more democratic than authoritarian, 3) permissive, and 4) uninvolved parenting. Of these four, authoritative parenting tends to result in children who are more happy, capable, and successful._[5]
While all children grow and develop in similar patterns, each child develops at his or her own pace._[8]
The first five—and especially the first three years—of a child’s life are the most important. They shape the brain’s organization, development, and functioning throughout life._[8]

Kids don’t remember what you try to teach them. They remember what you are.

- Jim Henson

Permissive parenting tends to result in children who rank low in happiness and self-regulation. They are more likely to experience problems with authority and perform poorly in school._[5]
There are four different types of development milestones for children: 1) physical (large- and fine-motor kills), 2) cognitive (ability to think, learn, and solve problems), 3) social and emotional (understanding of their own and others’ emotions), and 4) communication milestones (both linguistic and nonverbal communication)._[5]
The most common type of developmental delay in children is language and speech problems. Speech refers to verbal expression, such as the way words are formed. Language is more broad and includes expressing and receiving information, such as understanding gestures._[5]
Common causes of social and emotional developmental delays include autism, Asperger syndrome, and childhood disintegrative disorder. Some early signs of autism includes lack of eye contact, refusal to cuddle, and apathy toward parents or caregivers._[5]
Infant educational television does not promote intellectual development, because infants respond to things that respond to them. Even the most advanced DVD does not respond to the specific cues of an infant. Playing with a baby is far more valuable than even the most expensive system of videos._[1]
Studies show that children do best when they have at least three loving and supportive adult influences in their lives._[1]
Children who watch more than three hours of television, videos, or DVDs a day have a higher chance of conduct problems, emotional symptoms, and relationship problems by the time they are 7 than children who do not._[4]

Spanking remains a controversial child rearing practice

Studies show that corporal punishment can hinder intellectual development. In other words, there is a marked correlation between spanking and a lowered IQ._[5]
Maternal stress can affect fetal development, including an increased chance of cleft palate, depression, attention deficits, and distractibility. Stress hormones released by the mother can also reduce the placenta’s ability to protect the fetus from stress hormones in the future._[2]
One of the biggest threats to a developing fetus is maternal malnutrition, whether caused by famine, poverty, or dieting._[2]
Like many animals, people are not hardwired to be a good fit to their specific environment at birth. Instead, babies arrive with skills required to adapt to a wide range of conditions, which allows them to survive all over the world._[5]
About 100 years ago, 40% of American infants did not crawl. Instead, they crabbed on their backs, hitched, or log rolled to avoid tripping on the long gowns that babies wore during that era._[5]
Babies exhibit the palmar grasp, which happens when someone strokes the infant’s palm or puts anything in its hand. In 1891, one scientist tested how long a baby could grasp a bar. Most were able to hang on for at least several seconds, while one lasted 2 minutes and 35 seconds._[2]
At around the 28th week of pregnancy, babies can begin to smell the same smells as their mother. In fact, the amniotic fluid enhances a baby’s smell._[2]
At about 18 months, a toddler’s spoken vocabulary explodes, adding new words at about one every two waking hours. By age 6, it understands about 13,000 words (compared to an adult’s 60,000), though it usually doesn’t speak that many._[2]
While a toddler’s exclamation of “mine” may seem to be selfish refusal, it actually indicates a cognitive achievement of selfhood. They are beginning to understand that other people are separate entities._[2]
Babies begin to startle in utero around the 23rd week. However, if the same noise is repeated often, the baby will get used to it and stop startling._[2]
Babies whose parents talk to them frequently know 300 more words by age 2 than babies whose parents rarely speak to them._[3]

A child from a professional family will likely hear a million or more words than a poor child

A baby begins to “breathe” at around the 27th week, when its fluid-filled lungs start to expand and compress due to the rhythmic contractions of the mother’s diaphragm and chest muscles._[5]
Babies are born with the ability to taste sweet, bitter, and sour; however, they can’t taste salt until they’re 4 months old, when sodium-sensitive receptor proteins begin to emerge in the taste buds. The development to taste may correspond to the development of the kidneys._[5]
A baby’s eyes are about 75% of adult size, but its vision is blurry at 20/400. A baby’s vision should improve to 20/20 by 6 months old._[2]
About 90% of kids are right handed. There are more lefties in the U.S. than in other cultures, especially in cultures that view left-handedness as taboo._[5]
Between ages 1 and 2, a toddler’s cerebral cortex adds more than 2 million new synapses (connections between brain cells) every second. By age 2, they have more than 100 trillion synapses, the most they’ll ever have in their life. By the time they are adults, more than 50% of those synapses are gone._[2]
Children can’t remember much before the age of 3 due to what psychologists call “infantile amnesia.”_[2]
Babies can distinguish cats from dogs, something that is extremely difficult to program into a computer._[8]
Babies see in two dimensions until 2–4 months old. After this, an infant’s cerebral cortex matures enough to merge input from both eyes, which results in 3D vision._[12]
A child learns to pump on a swing around 4–5 years old._[12]
A child’s sense of privacy usually begins around 8–9 years old._[12]

Outdoor play is a critical and natural part of child development

Children who spend more time outdoors are less likely to become myopic. One study found that two hours per day of outdoor activity reduces the risk of myopia by about a factor of four compared with less than one hour per day._[2]
Scientists believe that even before birth, boys’ and girls’ brains develop differently—though they are quick to note that there’s no such thing as a completely male or female brain. A person’s brain is a mosaic of male and female._[11]
Male babies are born with as much testosterone as a 25-year-old man. After birth, testosterone levels plummet until puberty._[11]
While females produce some testosterone before they’re born, they don’t produce nearly as much as a male. Additionally, the estrogen a female fetus makes barely influences her developing brain, leading scientists to claim that girls have the brain a boy would have had if a boy’s brain weren’t changed by testosterone._[11]
Social interaction increases the speed and accuracy of learning in all ages, including babies._[6]
Holding and stroking an infant helps release hormones that are important for its growth._[9]
If babies’ bodies grew at the same rate as their brains, they would weigh 170 pounds by 1 month old._[10]
From ages 3–8, children’s brain tissue uses twice as much energy as adult brain tissue. A 5-year-old child weighing 44 pounds requires 860 calories a day. Half of that energy goes to the brain._[2]
Children can begin to organize information in their memory starting at about age 7._[2]
Just before and after birth, as many as 40,000 new synapses are added every second to a baby’s brain._[2]
A baby’s brain reaches 70% of its adult size by the first birthday and 80% by the second birthday._[2]
Multiple studies have shown that infant TV watching is correlated with poor language development. Two or more hours per day of screen time before the first birthday is associated with a six-fold increase in language delay._[2]
One in eight U.S. children between the ages of 6 and 10 has some hearing loss. A baby’s hearing is most easily damaged by noise exposure in the last trimester and the first six months of life. Premature babies are especially vulnerable to noise-induced hearing loss._[2]
Flavor preferences learned in infancy can last for years._[2]
Girls who eat regular family meals in a pleasant atmosphere are less likely than average to develop an eating disorder and become overweight._[2]
Playing is the most effective way for children to learn life skills and find out what they like._[2]

Babies and young children learn and imagine more than scientists previously believed

Preschool children’s ability to resist temptation is a much better predictor of eventual academic success than their IQ scores. Additionally, children who are skilled at behavioral self-control show less anger, fear, and discomfort and higher empathy than their peers who are not._[2]
In the U.S., the average baby starts watching TV at 5 months old. Before seventh grade, 82% of children are online._[5]
Parents who are more sensitive to their infants’ needs and respond quickly to emotional cues tend to raise children who are better at regulating their own emotions._[2]
While playing classical music isn’t likely to help their brain development, having children play or sing the music can increase visual, motor, attention, and mathematical skills._[12]
In order to stand upright, human pelvis are small, which means human babies are born earlier than they would be otherwise. Accordingly, some pediatricians label a baby’s first 3 months of life as the “fourth trimester” of pregnancy._[12]
All babies, no matter how responsive their parents are, have a period of peak crying around the gestation age of 46 weeks. (Most babies are born between the 38th and 42nd week.)_[2]
When babies imitate the facial expressions of their caregivers, it triggers the emotion in them as well, which helps infants build on their basic innate understanding of emotional communication. This may also explain why parents typically exaggerate their facial expressions directed at their babies._[2]
“Parentese,” or baby talk, is a seemingly instinctual response that researchers have found is critical to the development of an infant. Its exaggerated musicality and slow structure emphasizes the parts of language, which helps a baby grasp words._[2]

Childhood bullying can impact mental, physical, and social well-being even decades later

Bullying can have negative effects on a child’s development that can last well into middle age. Children who are bullied, especially those who are frequently bullied, are at risk for a wide range of poor social, health, and economic outcomes. Even occasional bullying increases the risk of depression, anxiety, and suicide later in life._[2]
According to renowned child educator Maria Montessori, knowing how to arrange an interesting, beautiful environment for children is as much a part of their development as knowing how to select fine children’s books for their library._[5]
By kindergarten, a child’s brain has reached its full size but it won’t stop developing until the mid-20s. Even then, the brain never stops changing, either for better or worse._[2]
According to Sigmund Freud, psychological development in childhood takes place in five stages: 1) oral/0-1 years, 2) anal/1-3 years, 3) phallic/3-6 years, 4) latency/6 years to puberty; and 5) genital/puberty-adult._[7]