18-Month Sleep Regression: What to Expect and How to Cope

Your 18-month-old was finally sleeping well—and then everything fell apart. Bedtime battles, night wakings, nap refusals, early mornings. Welcome to the 18-month sleep regression, one of the most challenging phases for many parents.

Understanding what's driving this regression can help you cope and come out the other side.

What Causes the 18-Month Regression? AAP

Developmental explosion:

Language development:

• Vocabulary is expanding rapidly
• Brain is working overtime processing words
• May "practice" talking at bedtime
• Wants to communicate more

Autonomy and independence:

• "I do it myself!" phase begins
• Toddler wants control
• Resists anything parent-led (including sleep)
• Says "no" to everything

Separation anxiety:

• Peaks around 18 months
• Understands you exist when gone
• Hates when you leave the room
• Calls for you at night to check you're there

Nap transition:

• May be dropping to one nap
• Schedule is in flux
• Can create overtiredness or undertiredness

Motor development:

• Walking is becoming running
• Climbing everything
• May try to climb out of crib
• Body is very active

Signs of the 18-Month Regression NSF

Sleep changes:

• Fighting bedtime (taking an hour+ to fall asleep)
• Waking at night (multiple times)
• Crying when you leave the room
• Refusing naps
• Early morning waking
• Shorter naps

Behavioral signs:

• More tantrums than usual
• Extra clingy
• Saying "no" to everything
• Testing every boundary
• More emotional

Duration:

• Typically lasts 2-6 weeks
• Can be longer if not addressed
• May blend into normal toddler behavior if it goes on

Why This Regression Is Hard AAP

Toddlers are mobile:

• Can stand and protest loudly
• May try to climb out of crib
• Can open doors and come to your room
• More difficult to contain

Toddlers have opinions:

• Will tell you they don't want to sleep
• Have words to ask for things
• Can negotiate ("one more book!")
• Are very persistent

Toddlers test limits:

• Developmentally, they NEED to test boundaries
• Sleep is a prime opportunity
• They want to see if rules are real
• Will push until they find the limit

Parents are tired:

• You've been doing this for 18 months
• You thought sleep was "solved"
• It's demoralizing to regress
• May give in out of exhaustion (which prolongs it)

Coping Strategies NSF

For bedtime battles:

Keep routine consistent:

• Same steps, same order, same timing
• Even if toddler resists
• Routine provides security
• Don't let battles extend routine length

Offer limited choices:

• "Blue pajamas or red?"
• "Two books or three tonight?"
• "Do you want to walk to bed or hop?"
• Gives control without giving in

Stay calm and firm:

• Don't negotiate extensively
• "It's bedtime. I love you. Goodnight."
• Engaging in battle gives toddler attention for protesting
• Boring responses work better

Connect before bed:

• Extra one-on-one time during day
• Quality time during bedtime routine
• Fill their connection tank so they don't seek it at 2 AM

For night wakings:

Brief, boring responses:

• Go to toddler, reassure briefly, leave
• "It's nighttime. Time to sleep."
• Don't turn on lights, don't have conversations
• Return to bed, repeat as needed

Don't start new habits:

• Don't bring toddler to your bed (unless you want to)
• Don't start milk or feeding at night
• Regression is temporary; habits can become permanent

Check for underlying issues:

• Is toddler sick?
• Teething (molars come around 18 months)?
• Something changed in environment?

For nap refusals:

Is toddler transitioning to one nap?

• If fighting second nap, may be ready for one nap
• Move single nap to midday
• Earlier bedtime to compensate

If not ready for one nap:

• Keep offering nap at consistent time
• Dark room, white noise
• May just be regression phase—keep trying

Stay consistent:

• Even if toddler doesn't sleep, offer quiet time
• Some days may nap, some may not
• Will even out once regression passes

Schedule Adjustments AAP

18-month-old typical schedule:

*If still on two naps:*

• 6:30 AM - Wake
• 9:30 AM - Nap 1 (1 hour)
• 2:00 PM - Nap 2 (1 hour)
• 7:00 PM - Bedtime

*If on one nap:*

• 6:30 AM - Wake
• 12:00 PM - Nap (2-3 hours)
• 7:00 PM - Bedtime

Adjustments during regression:

• Earlier bedtime if overtired
• Don't let nap go past 3:30-4:00 PM
• Watch wake windows (5-5.5 hours typical)
• Earlier bedtime is usually better than later

Handling Separation Anxiety AAP

During the day:

• Practice short separations
• Play peek-a-boo
• "I'll be right back" and always come back
• Build trust that you return

At bedtime:

• Reassure you're nearby
• "I'll check on you in two minutes"
• Follow through with check
• Use comfort object for when you're gone

At night:

• Go to toddler, reassure briefly
• "Mommy/Daddy is here. You're safe. Time to sleep."
• Keep it brief—don't linger
• Toddler needs to learn you always come back

Common Mistakes During Regression

Giving in to delay tactics:

• One more book becomes five more books
• "One more hug" becomes endless hugs
• Creates expectation that protesting gets results

Inconsistency:

• Different responses on different nights
• Different responses from different parents
• Confuses toddler about what to expect

Starting new habits out of desperation:

• Bringing toddler to bed with you
• Lying with toddler until they sleep
• Night feeding when not needed
• These can outlast the regression

Thinking it will never end:

• It WILL end
• Consistent response speeds resolution
• 2-6 weeks is typical
• You will sleep again

When Toddler Tries to Climb Out of Crib AAP

This is common around 18 months:

Safety first:

• Lower crib mattress to lowest position
• Remove anything toddler could climb on
• Consider sleep sack to limit leg movement
• If toddler gets out, it's time for toddler bed

Transition to toddler bed:

• If toddler is consistently climbing out, transition
• Toddler bed or mattress on floor
• Ensure room is completely safe
• May need baby gate on doorway

New challenges with toddler bed:

• Toddler can now get out freely
• May come to your room
• May play instead of sleep
• Silent return technique: walk back to bed without engaging

What Other Parents Ask

Q: Is this really a regression or is it just toddler behavior now?
A: The 18-month regression is a real developmental phenomenon. However, if sleep issues continue beyond 6 weeks without improvement, it may have become a habit. Consistent intervention is key either way. NSF

Q: Should I sleep train during the regression?
A: If toddler was sleeping well before and this is truly regression, consistent responses should help. If sleep was never good, you may want to implement a sleep training method now. Many methods work for toddlers with modification.

Q: My toddler suddenly won't nap. Has she dropped her nap?
A: 18-month-olds still need a nap (usually 1.5-3 hours). Nap refusal during regression is common. Keep offering nap consistently. Most toddlers don't drop naps until 3-4 years old. AAP

Q: How long will this last?
A: Most 18-month regressions resolve in 2-6 weeks with consistent response. Without consistent response, patterns can continue indefinitely.

Q: Is this regression worse than the others?
A: For many parents, yes. Toddlers are verbal, mobile, and opinionated. They can really test your limits. The good news: your response can shorten the regression significantly. AAP

The Bottom Line

The 18-month sleep regression is driven by major developmental changes: language, independence, separation anxiety, and possibly nap transition. It's one of the most challenging regressions, but with consistent, calm responses, it will pass.

Key points:

• Caused by developmental changes around 18 months
• Typically lasts 2-6 weeks
• Toddlers are testing boundaries—hold firm
• Stay consistent with responses
• Don't start new habits out of desperation
• Earlier bedtime often helps
• Separation anxiety: reassure briefly, then leave
• It will pass—hang in there

Clara is here to help you get through this challenging phase.