It’s a question every parent has whispered in the dark: “Why won’t my baby sleep?” You’ve done everything right — the cozy bath, the bedtime story, the lullaby — yet your little one seems determined to stay awake. You’re not alone. Many babies go through phases of resisting rest, and understanding why can make bedtime a little less stressful for everyone.

Key Takeaways

• Overtiredness: Staying awake too long triggers stress hormones like cortisol, making it harder to settle down.
  

• Under-tiredness: If wake windows are too short, babies may not have built enough “sleep pressure,” resulting in shorter sleep phases.
  

• Developmental Leaps: Learning to roll, sit, or crawl can disrupt sleep as babies practice new skills.
  

• Environmental Factors: Temperature, lighting, or noise can make it difficult to relax.

• Separation Anxiety: Around six months, babies begin to realize when parents leave — and may protest bedtime.

Why Babies Fight Sleep

When your baby resists sleep, it’s not defiance — it’s development. Babies’ brains and bodies are constantly changing, and sometimes sleep just doesn’t fit into their plans.

Overtiredness often catches parents off guard. When babies are awake too long, their bodies release stress hormones like cortisol and adrenaline, which make falling asleep even harder (American Academy of Pediatrics, 2022). It’s like a “second wind” — but not the happy kind. This is exactly what happens to adults when we’re exhausted but cannot seem to fall asleep- we’re “overtired and wired.” However, a baby has no ability to reason their way through this biological shift in sleep changes. 

On the other hand, not being tired enough can also cause bedtime battles. If your little one hasn’t had enough awake time, stimulation or activity, they simply may not be ready for rest. Your baby will slowly begin to be able to stay awake for longer periods of time as they grow and develop. As these wake windows lengthen with age, adjusting your routine can help align sleepiness with bedtime.

Developmental milestones are another big factor. Around six months, separation anxiety often begins, and babies crave closeness. At the same time, mastering new skills like rolling or crawling can keep them wide awake — their brains are too busy learning to switch off (Sleep Foundation, 2024). Giving them ample time to practice during their wakeful periods will prevent late-night party sessions.

Environmental discomfort — like a too-warm room, itchy clothing, or bright light — can also interfere with sleep. And of course, illness or overstimulation from an exciting day can make it difficult to wind down. Keeping the environment sleep-inducing is your first step to preventing sleep resistance. 

Recognizing the Signs of Sleep Resistance

You’ll know your baby is fighting sleep if you notice:

• Intense fussiness or crying at bedtime
  

• Arching their back or pushing away
  

• Waking immediately after being put down

• Waking more frequently throughout the night than usual
  

• Needing constant rocking, feeding, or holding to fall asleep
  

These signs often point to a deeper cause — not stubbornness. Look for patterns to find what’s keeping your baby awake.

💡 HALO Tip: For babies who need extra comfort while adjusting to independent sleep, try a HALO® SleepSack® Swaddle. It offers a womb-like sense of security while maintaining safe sleep practices.

How to Help Your Baby Sleep Better

If your newborn won’t sleep, start with the basics:

• Establish a predictable bedtime routine. Even simple cues — bath, massage, lullaby — help signal it’s time to rest.
  

• Watch for sleepy cues. Rubbing eyes, red eyebrows, or looking away are early signs of tiredness. Combine any of the above with a big yawn and you are in the perfect sleepy window.
  

• Create a calming environment. Keep the room dark, cool (68–72°F), and quiet with white noise if needed.
  

• Focus on comfort. Make sure baby’s clothing fits well and the mattress is firm, flat, and clear of any loose bedding, bumpers, pillows, or bumpers.
  

For newborns, hunger and overstimulation are two of the most common culprits. Feeding frequently, burping well, and limiting activity before bed can go a long way toward smoother nights.

Featuring HALO Full Size Breathable Mesh Crib in Slate Blue

Safe Sleep: The Foundation of Rest

Before anything else, safety matters most. The American Academy of Pediatrics (AAP) emphasizes these safe sleep recommendations (AAP, 2022):

• Place your baby on their back for all sleep.
  

• Use a firm, flat mattress with only a fitted sheet — no pillows, blankets, or toys.
  

• Room share (not bed share) for at least the first six months.
  

• Keep the sleep space cool, quiet, and clutter-free.
  

A secure, comfortable sleep space helps your baby rest easier and gives you peace of mind.

When to Talk to Your Pediatrician

If your baby’s sleep struggles persist despite your best efforts, reach out to your pediatrician — especially if you notice:

• Major changes in feeding or mood
  

• Signs of illness or pain
  

• Very few wet diapers
  

• Difficulty breathing, persistent crying, or extreme fussiness
  

It’s important for your pediatrician to first rule out medical issues. Then they may be able to suggest individualized strategies for better sleep or refer you to a trusted pediatric sleep consultant to help with a behavioral sleep program.

Sleep Safe, Sleep Sound

Building healthy sleep habits takes time — and patience. Remember:

• Stick with consistent routines.
  

• Respect age-appropriate wake windows.
  

• Maintain a safe, calm sleep space.
  

Every baby is different, but with consistency, compassion, and safe sleep practices, better rest is within reach.

💤 Explore HALO’s safer sleep collection to help your baby drift off peacefully — from our trusted SleepSack® Swaddles to wearable blankets that keep your little one cozy and secure.

References

• American Academy of Pediatrics. Safe Sleep and Your Baby: How Parents Can Reduce the Risk of SIDS. 2022.
  

• Sleep Foundation. Baby Sleep Patterns and Development. Updated 2024.

• Centers for Disease Control and Prevention (CDC). Infant Sleep Safety Guidelines. 2023.