Lying and Fibbing in Toddlers
Medically reviewed by Dr. Emily Torres, PhD, CCC-SLP · Pediatric Speech-Language Pathologist
Content reviewed against published AAP, NIH, CDC guidelines
Last reviewed:
Behavioral development varies greatly from child to child. If you have noticed lying and fibbing in toddlers, here is what you need to know.
The short answer
When a toddler tells a fib, such as denying they took a cookie or blaming a sibling, it is actually a sign of advanced cognitive development. Lying requires understanding that other people have different knowledge than you do, which is a sophisticated brain skill called "theory of mind." Most children begin experimenting with lying around ages 2-3, and this is a normal and even healthy milestone.
Key takeaways
- When a toddler tells a fib, such as denying they took a cookie or blaming a sibling, it is actually a sign of advanced cognitive development. Lying requires understanding that other people have different knowledge than you do, which is a sophisticated brain skill called "theory of mind." Most children begin experimenting with lying around ages 2-3, and this is a normal and even healthy milestone.
- Usually normal when: Your toddler denies something obvious, like having chocolate on their face while denying they ate the chocolate
- Call your doctor if: Your child is fabricating stories about being hurt or abused, which should always be taken seriously and evaluated by a professional regardless of whether you believe it is true
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to AAP, NIH, CDC guidelines, when a toddler tells a fib, such as denying they took a cookie or blaming a sibling, it is actually a sign of advanced cognitive development. Lying requires understanding that other people have different knowledge than you do, which is a sophisticated brain skill called "theory of mind." Most children begin experimenting with lying around ages 2-3, and this is a normal and even healthy milestone. At 12-24 months, children under 2 do not truly lie because they lack the cognitive ability to understand that others have different thoughts and knowledge. What may look like lying at this age is usually a child saying what they wish were true, not understanding the question, or parroting a response. If your 18-month-old says "no" when asked if they took the toy, they may simply be using their favorite word rather than deliberately deceiving. It is generally considered normal when your toddler denies something obvious, like having chocolate on their face while denying they ate the chocolate. However, you should contact your pediatrician promptly if your child is fabricating stories about being hurt or abused, which should always be taken seriously and evaluated by a professional regardless of whether you believe it is true.
Normal vs. Concerning
By Age
What to expect by age
12-24 months
Children under 2 do not truly lie because they lack the cognitive ability to understand that others have different thoughts and knowledge. What may look like lying at this age is usually a child saying what they wish were true, not understanding the question, or parroting a response. If your 18-month-old says "no" when asked if they took the toy, they may simply be using their favorite word rather than deliberately deceiving.
24-36 months
This is when genuine first fibs emerge. Around age 2-3, children begin to understand that you did not see what they did, and they experiment with saying things that are not true, usually to avoid getting in trouble. These lies are transparent and clumsy, which is endearing and normal. Research shows that children who lie earlier tend to have stronger cognitive and social skills. Responding with gentle honesty rather than harsh punishment encourages truthfulness over time.
3-4 years
Lying becomes more frequent and more skilled around ages 3-4 as theory of mind develops further. Children may tell elaborate stories, deny obvious transgressions, or blame imaginary friends. The best approach is to avoid setting "traps" by asking questions you already know the answer to, model honesty, and praise truthfulness when you see it. Occasional lying at this age is not a character flaw; it is a cognitive exercise.
What to Tell Your Pediatrician
- Describe when you first noticed lying and fibbing in toddlers and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your child lies constantly and compulsively about things that have no benefit, going well beyond normal developmental fibbing.
- Mention if lying is paired with other persistent behavioral concerns such as extreme aggression, cruelty to animals, or fire-setting in an older child.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Your toddler denies something obvious, like having chocolate on their face while denying they ate the chocolate
- Your child makes up fantastical stories that blend imagination and reality, which is creativity rather than deception
- Lying is occasional and primarily motivated by avoiding trouble or getting something they want
- Your child is otherwise honest in many interactions and the lying is not constant or calculated
- Your child lies constantly and compulsively about things that have no benefit, going well beyond normal developmental fibbing
- Lying is paired with other persistent behavioral concerns such as extreme aggression, cruelty to animals, or fire-setting in an older child
- Your child seems genuinely unable to distinguish between reality and fantasy by age 4, even when gently guided
- Your child is fabricating stories about being hurt or abused, which should always be taken seriously and evaluated by a professional regardless of whether you believe it is true
- Lying is accompanied by significant behavioral changes, withdrawal, fearfulness, or signs that something may have happened to your child
What You Can Do at Home
- Keep track of when you notice lying and fibbing in toddlers — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that your toddler denies something obvious, like having chocolate on their face while denying they ate the chocolate — this is generally within the range of normal.
- At 12-24 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Respond consistently and calmly to your baby's behavior. Maintain predictable daily routines.
- While monitoring at home, seek immediate care if your child is fabricating stories about being hurt or abused, which should always be taken seriously and evaluated by a professional regardless of whether you believe it is true.
Related Resources
Frequently asked questions
Is lying and fibbing in toddlers normal?
When should I call the doctor about lying and fibbing in toddlers?
When is lying and fibbing in toddlers normal?
What causes lying and fibbing in toddlers?
What should I mention to my pediatrician about lying and fibbing in toddlers?
Is lying and fibbing in toddlers normal at 12-24 months?
Is lying and fibbing in toddlers normal at 24-36 months?
Should I go to the ER for lying and fibbing in toddlers?
Does lying and fibbing in toddlers go away on its own?
References
- [1]American Academy of Pediatrics. Why Children Lie and What Parents Can Do About It. HealthyChildren.org. AAP
- [2]National Institutes of Health. The Development of Lying in Young Children. Developmental Psychology. NIH
- [3]Centers for Disease Control and Prevention. Positive Parenting Tips: Preschoolers (3-5 years). CDC
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Lying and Fibbing in Toddlers.
Things to mention
- Describe when you first noticed lying and fibbing in toddlers and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your child lies constantly and compulsively about things that have no benefit, going well beyond normal developmental fibbing.
- Mention if lying is paired with other persistent behavioral concerns such as extreme aggression, cruelty to animals, or fire-setting in an older child.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Your child lies constantly and compulsively about things that have no benefit, going well beyond normal developmental fibbing
- Lying is paired with other persistent behavioral concerns such as extreme aggression, cruelty to animals, or fire-setting in an older child
- Your child seems genuinely unable to distinguish between reality and fantasy by age 4, even when gently guided
Urgent signs to report immediately
- Your child is fabricating stories about being hurt or abused, which should always be taken seriously and evaluated by a professional regardless of whether you believe it is true
- Lying is accompanied by significant behavioral changes, withdrawal, fearfulness, or signs that something may have happened to your child
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of lying and fibbing in toddlers are normal. Talk to your pediatrician if your child is fabricating stories about being hurt or abused, which should always be taken seriously and evaluated by a professional regardless of whether you believe it is true.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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