If you’ve ever watched a baby suddenly stop crying the moment they’re picked up… or “pretend” not to hear you calling their name… or hide a snack behind their back with suspicious determination, you may have wondered: Wait—are babies actually lying?
It sounds wild, but modern research suggests that even before their first birthday, some babies are already experimenting with the earliest forms of deception. Not full-blown, morally questionable lying—but tiny, adorable, developmentally fascinating acts of trickery.
Let’s take a relaxed, science‑backed tour through what researchers have discovered about these miniature masterminds.
Babies and Deception: What the 2026 Study Found
In 2026, a large study led by Professor Elena Hoicka at the University of Bristol made headlines because of one surprising finding: About a quarter of babies show some form of “deceptive behavior” by 10 months old.
The research team surveyed 750 parents across the UK, US, Australia, and Canada. Parents reported behaviors such as:
- Pretending not to hear their parents
- Hiding toys
- Eating forbidden food out of sight
- Crying to get attention, then stopping instantly once picked up
Some parents even said their babies showed hints of deception as early as eight months.
Now, to be clear: these aren’t “lies” in the adult sense. Babies aren’t plotting elaborate schemes or crafting alibis. Instead, these behaviors are early experiments in understanding how their actions influence others.
But still—pretty impressive for someone who can’t walk.
Why Would a Baby “Lie”?
To understand this, we need to look at what psychologists call Theory of Mind—the ability to understand that other people have thoughts, beliefs, and perspectives different from your own.
Classic developmental research (including work by Kang Lee, a leading expert on children and deception) shows that lying requires some understanding of what another person knows or expects.
Babies don’t have a full Theory of Mind yet, but they do start experimenting with cause and effect:
- If I cry, someone comes.
- If I hide this toy, no one else can take it.
- If I look away, maybe they’ll think I didn’t hear them.
These aren’t moral decisions—they’re strategies. Babies are tiny scientists, constantly testing what works.
Early Deception Isn’t a Bad Sign—It’s a Developmental Milestone
One of the most important takeaways from the 2026 study is this:
Early deceptive behavior is normal, healthy, and expected.
It shows that babies are:
1. Learning social rules
They’re figuring out how people react to different behaviors.
2. Developing problem‑solving skills
“Hiding the cookie” is basically a baby’s version of strategic thinking.
3. Building the foundations of communication
Even nonverbal deception requires understanding how others interpret actions.
4. Practicing independence
Sometimes a baby just wants to do their own thing—and they’re learning how to make that happen.
So if your baby occasionally acts like a tiny con artist, don’t panic. It’s a sign their brain is growing exactly as it should.
How Baby “Lies” Compare to Older Children’s Lies
While babies show early hints of deception, preschoolers are the true experts.
Decades of research summarized by Kang Lee (University of Toronto) shows that:
- Children begin telling verbal lies around age 3
- Their lies become more convincing as they grow
- Lying is linked to cognitive skills like working memory and mental state understanding
By comparison, baby deception is:
- Nonverbal
- Simple
- Opportunistic
- Not morally motivated
A baby isn’t thinking, “I must protect my reputation.” They’re thinking, “If I hide this, I get to keep it.”
Examples of Baby “Deception” (All Observed in Real Studies)
Here are some of the behaviors parents reported in the 2026 study:
1. The Selective Hearing Act
Parent: “Come here!” Baby: stares into the void like a philosopher contemplating the universe.
2. The Forbidden Snack Shuffle
Baby grabs something they shouldn’t eat… …walks behind the sofa… …silence.
3. The Toy Vanishing Trick
Sibling approaches. Baby hides toy behind their back. Sibling leaves. Baby triumphantly retrieves toy.
4. The “I’m So Sad” Performance
Baby cries dramatically. Parent picks them up. Baby immediately stops and smiles.
Are these lies? Not exactly. Are they clever? Absolutely.
Why This Research Matters
Understanding early deception helps scientists learn:
1. How social intelligence develops
Deception requires predicting how someone else will react.
2. How communication evolves
Even nonverbal trickery is a form of communication.
3. How early children understand rules
Breaking a rule secretly means they know the rule exists.
4. How to support healthy development
Recognizing these behaviors helps parents respond with guidance rather than worry.
So… Are Babies Little Liars?
Here’s the friendly, science‑approved answer:
Babies don’t lie the way adults do, but they do experiment with simple forms of deception as early as 8–10 months. These behaviors are normal, healthy, and part of learning how the social world works.
Think of it this way: Your baby isn’t trying to manipulate you—they’re trying to understand you.
And honestly? They’re doing a pretty impressive job.
Sources
University of Bristol study on early deception in infants, reported by The Guardian (2026).
Kang Lee, “Little Liars: Development of Verbal Deception in Children,” Child Development Perspectives (Oxford Academic).
Additional developmental psychology research on lying and Theory of Mind.