In the womb, all babies grow mustaches...that they eat. That's right, you heard me. When a fetus is about four months into pregnancy it develops a mustache that, over the course of a month, spreads over its entire body. This hair is called lanugo and it all falls out before birth if you're lucky and is EATEN BY THE BABY.

When you were born you had tastebuds on the roof, back, and sides of your mouth in addition to your tongue. They eventually fade with age, but that doesn't stop it from being really weird in the meantime, especially considering the mustaches they've recently eaten.

Girl babies get their period, and all babies have boobs and lactate. When babies are in the womb, they absorb their mom's hormones, so after they're born they've got some estrogen to sort through. That means that female babies shed their uterine lining, having a mini period, and all babies lactate a bit. Sometimes blood comes out of their nipples too in case you wanted to cringe even more about this whole ordeal. Horrifying, but true.

Babies' eyes are 75 their adult size when they're born. Now you won't be able to unsee the fact that baby eyeballs are gigantic compared to their heads. You're welcome!Oh, and upon birth, babies' vision is 20400 extremely near-sighted, but by the time they're six months old, it should be 2020.

Babies born in May weigh more. As if by some creepy medieval magic, babies born in the month of May weigh an average of 200 grams more than other months. Are they in cahoots with the moon? The Earth's rotation? No one knows, but everyone's freaked out by it.Okay, just I am.

Babies prefer female voices, and subconsciously adults adapt. That's probably why people find themselves talking in high-pitched tones when they're around babies. This phenomenon is sometimes called "Motherese," and it's obviously proof that BABIES CONTROL MINDS. Wake up, sheeple!Okay, probably not

Babies sleep with their eyes open. As if newborns weren't hard enough to take care of, when they finally fall asleep it's very common for babies' eyes to stay open and roll around in the sockets. So if your child starts doing this, the good news is that it isn't possessed. The bad news is that it's really freakin' creepy to watch.

Baby boys get erections...both inside the womb and when they're born If a woman tells you she's pregnant with a boy, that's her polite way of telling you "I am pregnant with a human who, in all likelihood, has a boner right now inside of my body as we speak." That's because baby boys get erections while they're in utero, and very commonly have one when they're born.

Babies don't have kneecaps. They just have a structure of cartilage that forms something like it, but the real kneecap doesn't develop until a few years into life. Other parts of the baby's skeletal system develop similarly. The older we get, the more those bones that begin as cartilage lose their "bounce," and falling becomes a lot more painful and a lot less nonchalant. Before that, we're basically miniature invincible cartilage demons.

The likelihood of having twins varies around the globe. In Nigeria, odds of having twins are 22-1. The West-African region is particularly prone to twins. In Japan, however, the odds are 200-1. If you don't think this is disconcerting, you clearly haven't thought about the logistical horror that is raising a pair of twins, and the obvious conclusion we can all reach that babies are globally conspiring to burden certain parts of the world with this albeit adorable horror.

Like so many classic villains, newborns don't actually cry tears. When you hear a newborn crying, they're actually just screaming. It isn't until the third week of their life or sometimes longer that they start to produce tears when they're crying. Regardless of tear production, though, a baby's cry is always loud enough to wake you up out of a sound sleep.

Babies can breathe and swallow at the same time. Up until seven months of age a baby is able to swallow and breathe simultaneously. This might seem random, but it's actually so that they can beat you in drinking contests, so never challenge an infant to a keg stand. Never.

The soft spot on a baby's head bulges and pulsates. The soft spot on a baby's head is called the fontanelle, and before the skull is fully grown in that spot it isn't just a squishy, sensitive area. It's also a creepy bulging crevice of doom if you look close enough. Is that the BRAIN coming out? THE BABY'S SOUL? Not really, but it's still horrifying to think so.

Babies have superhuman strength. You may know that newborns have the reflex to grab onto things with their hands, but what you probably didn't know is that their grasp is strong enough to hold their ENTIRE BODY UP. Picture an Olympic gymnast on the rings, but a newborn.

Baby poop is the perfect consistency to create the most amount of mess. Newborns may look cute, but the texture of their, ahem, production is the perfect storm of explosive feces. TheBump.com's Dr. Levine says, "Newborn poop is mostly liquid with some mustard-seed texture mixed in. As a result, it doesn't take much power to propel it across a room." Coincidence? I think not.

Babies conveniently forget all of the horror they put you through, and how weird they've been. Babies forget the majority of the first three years of their life. Neuroscientists call this "infantile amnesia" and have several theories about why this occurs, but we can all agree that regardless of why it happens, the result is that all of us adults are blissfully unaware of the completely bizarre things we did when we first entered this world, and the effect it had on others.