15 Weird Things Babies Do and Why They Do Them
Babies do some truly strange things—but most of them are completely normal.
Whether it’s staring off into space, shaking their heads for no reason, or letting out sudden cries in their sleep, new parents often wonder: Is this behavior okay?
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Why Understanding Weird Baby Behaviors Matters
Newborns and infants are constantly growing, changing, and adapting to life outside the womb. That means many behaviors that seem bizarre to adults are actually signs of development. Understanding these quirks can bring comfort and help you recognize what’s actually cause for concern—and what’s just another funny baby phase.
1. Startling for No Reason (Moro Reflex)
Your baby suddenly throws their arms out, opens their hands, and cries—often while asleep.
Why it happens: The Moro reflex is a normal neurological response to sudden stimuli like loud noises or a shift in position. It usually disappears by 4 months.
👉 Helpful product: Swaddle blankets can help prevent this reflex from waking them up.
2. Crossing Their Eyes
At random times, your baby’s eyes go cross-eyed—or even look in different directions.
Why it happens: Eye muscles are still developing. Most babies gain better control by 3–4 months.
👶 Linked post: Essential Items for 3 to 6 Month Old Babies »
3. Grunting, Snorting, and Noisy Sleep Sounds
Newborns are loud sleepers. You might hear grunts, squeaks, or snorts.
Why it happens: Their nasal passages are tiny, and their breathing systems are still maturing.
👉 Helpful product: A humidifier can keep airways clear and ease breathing.
4. Pooping With Intense Facial Expressions
Red faces, grunting, even crying—your baby looks like they’re in pain every time they poop.
Why it happens: Babies don’t yet know how to coordinate pushing with relaxing their pelvic floor muscles.
Tip: If the stool is soft, it’s not constipation—just dramatic delivery!
5. Shaking Their Head Side to Side
Especially during or after feeding, you may see your baby shake their head rapidly.
Why it happens: This helps them self-soothe and may also be linked to exploring neck muscles.
6. Jerky, Sudden Limb Movements
Their arms and legs flail suddenly and seemingly without cause.
Why it happens: The nervous system is still developing. These reflexes help strengthen muscles and neural connections.
7. Chewing on Everything
Their hands, your shoulder, the blanket—everything goes in the mouth.
Why it happens: Chewing is a comfort behavior and helps prepare for teething.
👶 Linked post: 5 Genius Teething Toys That Instantly Soothe Fussy Babies »
8. Staring at Lights or Ceilings
Your baby becomes mesmerized by a ceiling fan or the corner of the room.
Why it happens: Their developing brain is fascinated by contrast, light, and movement.
👉 Helpful product: A crib mobile with gentle light projection can offer safe visual stimulation.
9. Smiling in Their Sleep
That dreamy smile is heart-melting—but also confusing when it happens in deep sleep.
Why it happens: It’s likely a reflex, or part of REM sleep brain activity—not necessarily linked to dreams.
10. Kicking and Flailing While Feeding
Bottle or breastfeeding can turn into a mini wrestling match.
Why it happens: Babies often use movement to stimulate milk flow or express frustration.
Tip: Try calming the environment or changing feeding positions.
11. Scratching Their Own Faces
Tiny fingernails cause surprising scratches—often overnight.
Why it happens: Babies have little control over their hand movements early on.
👉 Helpful product: Baby mittens can prevent accidental scratches.
12. Sleeping in Strange Positions
Butts up in the air, arms flopped behind them—it all looks uncomfortable.
Why it happens: These positions mimic how they curled in the womb and are soothing to many babies.
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13. Making Choking or Gurgling Sounds While Eating
It can sound scary, but it doesn’t always mean trouble.
Why it happens: Your baby is still learning how to coordinate swallowing and breathing.
Watch for: Blue lips or ongoing coughing could signal an issue—talk to your pediatrician.
14. Laughing or Crying at Nothing
Sudden giggles—or tears—without a clear reason.
Why it happens: Emotional regulation is still developing. Even gas or tummy sensations can prompt these reactions.
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15. Fixating on One Object for a Long Time
Whether it’s a shadow, toy, or your earlobe—your baby stares for minutes on end.
Why it happens: They’re working hard to process and make sense of new visuals.
Development tip: High-contrast baby books are great at this stage.
👉 Helpful product: Black and white baby board books
When Should You Be Concerned?
Most of these behaviors are completely normal. But check with your pediatrician if you notice:
- Lack of eye contact by 3 months
- No response to loud sounds
- Excessive stiffness or floppiness
- Seizure-like movements
- Constant head banging past 6 months
Always trust your instincts—when in doubt, ask.
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❓ FAQ: Weird Things Babies Do
Is it normal for my baby to grunt and groan while sleeping?
Yes! Noisy sleep is completely normal in newborns. Their nasal passages are small, and their sleep cycles are still developing.
Why does my baby cross their eyes?
Babies’ eye muscles are still gaining control. Occasional crossing is normal for the first 3–4 months.
Why does my baby smile in their sleep?
This is likely a reflex or part of REM brain activity—it doesn’t necessarily mean they’re dreaming.
Should I be worried if my baby startles often?
Not at all. The Moro reflex is a natural response to stimulation and usually fades by 4 months.
Why does my baby shake their head side to side?
This is a self-soothing behavior and a way to explore motion. If it’s constant or paired with other issues, consult your pediatrician.
Final Thoughts
Babies are weird—in the most amazing ways. Almost all of these strange behaviors are just part of their growth and development. So take a deep breath, snap a photo of that upside-down sleeping pose, and know your little one is right on track.
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💬 Have you noticed any funny or weird baby behaviors? Share them in the comments below!
