Sleep-trained baby waking up again? The bad news is that babies can lose sleep for many reasons. The good news is that babies who are already sleep trained are easier to be trained again. Here are some of the most common sleep disruptors and can cause the sleep-trained baby to wake up, and a few tips for how to retrain your little one. 

Let me start by telling a real-life story that happened to one of my clients. For the sake of this article, we’ll call her Hanna. Hanna sleep-trained her son when he was five months old. 

She was so devoted and persistent that she managed to get her little one to start sleeping overnight and independently in a matter of a few days. However, six months later, her son stopped sleeping overnight. He would protest and cry and wake up several times every night. She was back at square one!

If you find yourself in the same situation, don’t be alarmed! This is entirely normal. In fact, many things can disturb a child’s sleep patterns. It can be something like learning to talk or walk, being sick, or even being away from home. Luckily, re-training your child is possible and it’ll be even easier than the first time.

Here are a few reasons why your sleep-trained baby is waking up again and tips on how to re-train him.

The most common sleep disturbers causing a sleep-trained baby to wake up

Gaining new motor skills

When a baby develops new motor skills such as walking or crawling, his body would require more calories to keep up. As a result, the baby may be constantly hungry and wake up often to feed. 

Another reason why a sleep-trained baby who’s gaining new motor skills might wake up at night has to do with the brain. While a baby is asleep, his brain is encouraging him to practice his newly developed abilities. If this is the case with your little one, he’ll be needing more help getting back to sleep. 


A breastfeeding baby may start waking up at night when his mother goes back to work. One reason is separation anxiety, meaning he wants to spend more time with his mother. Another reason is that the mother’s milk supply is decreasing, and the baby is not getting enough calories during feedings. If you suspect this may be the case with your child, schedule a weight check at your pediatrician’s office.

Changes in their normal routine

Sometimes, a change in your child’s normal routine can disturb his sleeping patterns. For example, you may have guests in the house, moved to another home, or are traveling. 

Sickness or pain

When kids are sick, they may wake up more frequently. This is usually due to discomfort from a congested head, tummy ache, etc. Your child may be waking up due to pain. There are many possible causes of pain in babies, including illness such as infections, colic, teething, or a physical injury. 

Dropping a daily nap

One of the signs that you dropped a nap too soon is your little one’s change in sleep patterns. He may start waking more at night because he can’t tolerate his maximum awake time yet, which then causes him to be overtired.

Tips for repeating sleep training

Stick with the same sleep training method

If the sleep training method worked the first time, stick to it. You may be tempted to try an alternative, but I’d advise sticking to the same one. Maybe you used the cry-it-out method and are skeptical about doing it all over again, but if you did it the first time, you’ll do it again! 

Be ready for some amount of crying

If you’re too scared about listening to your little one cry for you at night, there are some tips to survive these challenging days. One tip is to sleep train by shutting your baby’s door and listening from the outside. If the cry-it-out method is too hard on you psychologically, some gentler techniques can be applied, such as gradually decreasing the time you spend comforting him. 

Only sleep-train if the night wakings are tiresome for you

Know that there’s always the option to skip sleep training your child, especially if you can handle the crying and frequent night wakings. However, if you notice that his disturbed sleep patterns are taking a toll on your mental health, sleep training is of the essence. 

Know when to worry

If your baby is losing weight, refuses to breastfeed or drink from a bottle, loses energy, or becomes very sleepy or fussy, it may be time to see a doctor. A visit to the pediatrician can ensure you’re not missing anything like an ear infection.