Toddlers between ages 1 and 3 are going through enormous physical, cognitive, and emotional changes, and nearly all of those changes can disrupt sleep. The good news: most toddler sleep problems have identifiable causes and straightforward fixes. Children ages 1 to 2 need 11 to 14 hours of sleep per 24 hours (including naps), and children 3 to 5 need 10 to 13 hours. If your toddler is falling short of those numbers, one or more of the factors below is likely at play.
Their Brain Is Developing Faster Than They Can Handle
Toddlerhood brings a surge in verbal skills, awareness of surroundings, and curiosity about everything. Your child is suddenly able to notice more, want more, and ask for more. That translates directly into bedtime resistance: “I need one more hug,” “I need a drink,” “I need to go to the bathroom.” These aren’t just stalling tactics (though they can be). They reflect a child whose expanding mind is genuinely more engaged with the world and less willing to disconnect from it.
At 18 months, emotional reactions deepen and cognitive functions like reasoning and problem-solving expand considerably. This often coincides with a well-known sleep regression. Several factors pile up at once: increased mobility and physical restlessness, a growing sense of independence that makes them push back against bedtime, and in some cases, the early stirrings of separation anxiety. Teething can also overlap with this window, though recent research suggests its effect on sleep is smaller than most parents assume. One study found no significant differences in sleep quality on teething nights compared to non-teething nights, while another found disruption limited to just the day of eruption and the following day.
Separation Anxiety Peaks in This Age Range
Separation anxiety is a normal developmental stage that typically begins between 6 and 12 months and gradually fades by around age 3. During this period, your toddler may insist on having you next to them while they fall asleep, cry when you leave the room, or wake repeatedly just to confirm you’re still nearby. This isn’t a behavioral problem. It’s a sign their attachment system is working exactly as it should.
The challenge is that separation anxiety can significantly increase the time it takes your child to fall asleep. If bedtime has turned into a prolonged negotiation where your toddler needs you physically present, you’re likely dealing with this. Brief, calm reassurance visits (rather than staying until they’re fully asleep) can help them build confidence that you’ll return, without reinforcing the idea that sleep only happens when you’re in the room.
The Crib-to-Bed Transition Changes Everything
Moving from a crib to a bed is one of the biggest triggers for toddler sleep problems. In a crib, your child is contained. In a bed, they have freedom, and they will use it. Expect visits to your room, trips to explore the hallway, and creative reasons to get up. This transition typically happens between ages 2 and 3, and it can take weeks for a toddler to adjust to the idea that a bed without walls still means staying put.
Screens Before Bed Suppress Their Sleep Hormone
Young children are far more sensitive to light before bedtime than adults. A study from the University of Colorado Boulder found that even dim light (well below the brightness of a typical room) suppressed the sleep hormone melatonin by an average of 78% in preschool-aged children. More striking: even 50 minutes after the light was turned off, melatonin had not rebounded in most of the children tested.
This means that a tablet, phone, or TV show in the hour before bed doesn’t just stimulate your toddler’s brain with content. It actively delays the biological signal their body needs to feel sleepy. If your child is watching anything with a screen in the last hour before bedtime, that’s one of the highest-impact changes you can make.
What They Eat in the Evening Matters
Diet plays a measurable role in toddler sleep. A large study of 2-year-olds found that high intake of soft drinks, snacks, and fast food was associated with a 37% increase in the odds of inadequate sleep and a 34% increase in night waking. Higher sugar, carbohydrate, and fat intake combined with lower fiber intake have also been linked to shorter sleep duration and more sleep disturbances in preschool-aged children. You don’t need to overhaul your toddler’s entire diet, but keeping the last meal or snack of the day relatively low in sugar can make a noticeable difference.
Night Terrors and Nightmares Look Very Different
If your toddler is waking up screaming, it helps to know which type of episode you’re dealing with, because the right response is different for each.
Night terrors involve partial waking. Your child may scream, thrash, kick, or even walk around, but their eyes, though wide open, don’t register your presence. They can’t be awakened or comforted during the episode, which typically lasts 10 to 30 minutes. In the morning, they usually have no memory of it. Night terrors are more distressing for parents than for the child.
Nightmares, by contrast, fully wake your child. They know they’re scared, they can describe what frightened them (at least vaguely), and they want comfort. Nightmares are more common in the second half of the night, during the heaviest dreaming phase. Reassurance and a calm presence are the right response here. For night terrors, the best approach is to stay nearby, make sure your child is safe, and wait for the episode to pass without trying to wake them.
A Consistent Bedtime Routine Is the Single Best Fix
Research consistently shows that a predictable bedtime routine leads to earlier bedtimes, less time lying awake, fewer night wakings, and more total sleep. The routine itself doesn’t need to be elaborate. A warm bath, brushing teeth, and reading a story is a well-supported sequence. What matters more than the specific activities is doing them in the same order, at roughly the same time, every night.
The benefits are dose-dependent. One night a week with a consistent routine is good. Three nights a week is better. Every night is best. And the younger you start, the stronger the effect. If you’ve been inconsistent with bedtime, simply adding structure, even a few nights a week, is one of the most evidence-backed steps you can take.
The Room Itself May Be Working Against You
Temperature is a common and overlooked factor. A room that’s too warm or too cool disrupts sleep; around 18°C (about 65°F) is the recommended target. A simple room thermometer takes the guesswork out of this. Background noise can also be a problem, especially if your toddler’s room is near a street, a living area, or a sibling’s room. White noise can help by masking unpredictable sounds that cause partial awakenings.
Darkness matters too, especially given how sensitive young children are to light exposure. Blackout curtains or shades can prevent early morning light from cutting sleep short, and keeping the room dim during the bedtime routine helps melatonin do its job.