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It Looks Weird, But Here's Why Your Baby Sleeps With Their Eyes Half Open *Shudders*

One of the things I've learned since becoming a mom is that kids can be creepy. If you've ever woken up in the middle of the night to see a tiny dark silhouette standing in your room staring at you, then you'll know exactly what I'm talking about. It's frightening to the point of feeling full regret over every scary movie you've ever seen. And have you ever seen a baby sleep with their eyes open? Yeah, zombie baby is a thing. So, if you're wondering why your baby sleeps with their eyes half open, I get it. You need an explanation, because it's slightly terrifying.

The first time I saw my son sleep with his eyes partially open, I couldn't help but stare. He looked weird — like a tiny little zombie baby. He was a good sleeper and did spend a lot of time sleeping with his eyes open like that, so I don't think I ever mentioned it to his pediatrician, but it looked creepy. Not to worry though — apparently this phenomenon is very common and in most cases, completely harmless. I checked in with pediatrician, CEO of Happiest Baby, and the creator of SNOO Smart Sleeper Dr. Harvey Karp, and certified sleep coach and founder of Bill Fish just to make sure.

Dr. Karp explains to Romper in an email, "When we sleep, we still use our muscles. Babies startle, roll, groan, and some even open their eyes while they are still asleep. Older babies can even have night terrors, which is a scary occurrence we see in preschoolers and elementary aged children. They may be screaming with their eyes fully open, but still totally asleep," which sounds completely terrifying.

Fish also tells Romper that while looking down at your baby sleeping with their eyes open might be startling, "it is completely natural for infants to sleep this way. Babies tend to sleep with their eyes open when they are in REM sleep, and babies are in REM sleep far more than adults in a normal sleep cycle." So while it's creepy to look at, being in REM sleep is exactly where you want your baby to be when they're taking a nap. In fact, an article on the First Cry Parenting website confirmed this and explained, "research suggests that this mode of sleeping is during the active phase of the sleep cycle, known as Rapid Eye Movement or REM. Newborn sleep consists of longer periods of REM than adults, making up over half of their entire sleep time. As they grow older, their sleeping patterns become more like adults, meaning they wake up less during the night and are less fussy during nap time."

If you're still wondering why this happens though, the same article breaks it down and explained that babies actually sleep with their eyes partly open for two reasons: genetics and medical. Sleeping with your eyes open may be hereditary and "you can look into your and your spouse’s family history to ascertain if anyone else sleeps with their eyes open. If you, your spouse, or immediate family members share this trait, it is very likely your baby will too."

Medical reasons, while this sounds more alarming, can actually be due to something called "nocturnal lagophthalmos" which is quite "harmless and does not continue for more than a year to a year and a half," explained the article. But in rare cases, "it might be because of thyroid problems, damaged facial nerves or even some tumors. If you find that your baby is unable to sleep with their eyes closed for extended periods of time, please consult your doctor."

Fish also recommended that "if your child continues to sleep with their eyes open past 18 months of age, it would be recommended to bring up the situation to your pediatrician." But overall, babies sleeping with their eyes partially open is normal and harmless. Dr. Karp agrees and says that while this phenomenon is completely harmless, you may want to seek an expert opinion if your child is "tired all day, or often waking in need of parents' attention," otherwise, let your little one dream on, even if it does look a little creepy.