Download a free audiobook version of Brit Bennett’s bestselling novel, “The Vanishing Half” at www.audible.com/ted-ed and follow the story of separated identical twins Stella and Desiree as they grapple with how their past decisions have shaped their identities.

That story of a mother's liver growing back from her baby's stem cells is the most wholesome thing I've every seen. Returning the gift of life.

“Babe, I didn’t cheat! I’m just a chimera!”

"So, who's your mom?" *"My mom was never born."*

I had a fraternal twin who sadly passed away in the womb. I always knew I have absorbed some of them as a fetus because I have an extra tooth, but I didn't know that it could be this severe, I could have whole organs with their DNA.. crazy

My grandmother has that. She has 2 different eye colours, a leg length discremency, and has 2 different shades of skin with a distinct line.

The mother can in this way get to know her unborn sister in some way, by observing her own children. Sad but beautiful.

My second child is a chimera. When I was pregnant with her, I had a ghost sac or she had a ghost twin. And then it disappeared. The two sacs became one. My oldest and my youngest have a blood disorder. She doesn’t … she’s the only one.

"When my mother was pregnant with me, they did an ultrasound and found she was having twins. When they did another ultrasound a few weeks later, they discovered that I had RESORBED the other fetus. Do I regret this? No. I believe his tissue made me stronger. I now have the strength of a grown man AND a little baby." SCHRUTE, Dwight. It all makes sense now lol

When you realise: you are your twin, but you two are together

It's mind blowing that even though her sister does not exist but has 2 biological children 🤯🤯🤯🤯

It's kind of beautiful to think of a baby's cells healing their mother many years later.

Mind-blowing. Can you imagine how many times in history this has happened without us knowing? How many family trees are in fact inaccurate?

"You could have a secret twin" My thoughts at 3 AM:

"You could have a secret twin" me to my twin sister: gurl, i think we're triplets-

so happy for the lady whose liver started regenerating, it's like her unborn baby left her one last token of love 😭💕💌

Imagine having 2 kids without being born.

I doubt we can ever repay the knowledge this channel has given to the world Edit: thanks for the likes people!

"you are NOT the father" crowds scream, dudes life ruined (just ended up being chimerism and maurys test wasnt able to pick it up)

Imagine what the mother would have felt, giving birth to two of her sister's kids and then realizing she is the sister herself.

I find this extremely interesting because I was a triplet and I absorbed my triplets. I always wondered what would happen if they were born.

Stem cell form baby regenerating the liver of mother seemed like a child rescuing mother in trouble, really wholesome ☺️

stories like this really make me feel like I carry a whole universe within me

Thats so cool. Imagine your liver is failing and your long born child is like: "I will never let you die, mother" and heals you all alone.

It can be mentally complicated to raise you’re unborn sister’s child… It can also be complicated to live with the fact that you would have a twin! Your life would be sooo different 😶

This is insane! Nature really is fascinating! 😲

Holy Cow there’s just so much we don’t know about ourselves even after all these years of technological advances

Gorgeous animation, good job to whoever was in charge of that !

I also heard about this story. Genetics is just incredible! I’m twin, he/she just died in the first stades of the pregnancy :/

Imagine being an unknown chimera and ending up on Maury show. "You are NOT the father! You're an uncle tho"

“The genes that make us who we are” sounds like a Levi’s commercial.

How would you determine which genome is actually yours? If the separate genomes can be spread throughout the body in different places which would you say is the twin?

"sweetie i dont cheat to your father its my twin" child: but mommy your twin was never born mom:😱😱

Biology is so interesting, i really love it.

Any day Ted-Ed posts a video is a good day. Much love from Brazil!

3:48 is the power house of the cell

Makes me wonder if people I know who look very different from their parents have a parent with chimerism. Fascinating!

“I believe his tissues has made me stronger. I now have the strength of a grown man and a little baby.” -Dwight Schrute

The story of the mother's liver regenarating really moved me since I lost my mom to liver failure due to cancer ,wish that knowledge could be used to help people

This is amazing. I got chills after it was revealed.

My husband has three different colors of hair... Mostly brown hair, but also some blonde and red. Blink, blink. When I was pregnant with my son, I could have sworn there was a twin... Now that I know that so many pregnancies start of as twins, maybe I was right. I had no idea!

What if my mom is my aunt? *becomes paranoid for the rest of my life* Thanks Ted-ed!

By the title alone I think a new fear is unlocked 😅

Great. Just 2 days ago I was watching a documentary about hand transplants which got me wondering, what happens to a person's DNA when they get an organ from another person. And KZfaq recommended me the answer today.

So that's why I had an imaginary friend back in my childhood. I haven't even able able to read back then, and suddenly spitted out a person name which my parent don't even recognize, and even playin with him.. damn I wish I could remember more about my childhood

Injecting your own baby’s stem cell to regenerate organ sounds like a technology with huge potentials .

House MD has an episode about chimerism. At the time when the series was shot, chimerism was considered very rare.

1 in 8 individual births start out as twins?! Unbelievable! That changes everything.

Everything is fine untill you found out your mom had a twin sister who was born.

TED-ED: "You could have a secret twin!" Me: "Is this about Chimerism?" TED-ED: "But not the way you think!" Me: "Guess not then"

I just wanna say, I really love the animation!

This art style is absolutely amazing-

Videos like these is the reason why I don't shut up aboth things I learn about here ...it's sooo mind blowing

The animation and music for this one is especially stellar. Excellent job and fascinating info

I'm surprised Karen didn't ask to see the manager of genomes.

This can mean a lot of things. She is a aunt and a mother to her kids. She is partial mother. Since those genes are hers. They only exist with her and are her cells. What quantifies her? I say she has 2 different genomes. Both belong to her and both was born with her.

I was a twin until 9 weeks and then I absorbed my twin best the doctor could see. My mom never bled. I have often wondered if I was a chimera. No real reason to test and not even sure how to ask for that.

I’ve heard of fetal cells regenerating maternal tissue before. It would be such a useful treatment for so many degenerative diseases! Sadly, toti-/pluri-/oligopotent cells will much more frequently cause tumorous growths rather than target and regenerate damaged tissue as we currently do not have a sufficiently in depth grasp of all the signaling and differentiation going on as well as just the general biology of “stem cells”

I really need to do further studies on this. I always wondered why I am slightly dual toned, like almost my left half is just so subtly a different shade of skin. I'm also slightly asymmetrical, and recently I was wondering about whether I'd absorbed a twin during my development. In fact, I asked my mother "Was I a twin during the first terms of the pregnancy?" And considering she didn't know anything about a twin, I might need to do some investigation! :D

I’m mostly just confused by why they assume which DNA belongs to who. If they are both present in her body, despite having a fraternal twin that she absorbed, how can you ever know who’s whose? For all we know, the two sons could be biologically hers and the one isn’t.

I just want to say, this video is BEAUTIFULLY animated. I absolutely loved it.

The animations are always amazing, but this is incredibly charming.

This is amazing. We think we know everything about ourselves yet there are mysteries yet to be explored. Thank you Ted, this was a great video.

Video: *says that chimerism can show up in hair and eyes* Me: *thinks about Shoto Todoroki from my hero academia*

okay but this animation style is genuinely beautiful? i dont know how to describe it it's just so . flowy and almost ethereal in a way. its mesmerizing

Wow, having an unborn person's child must be tremendous. Nature always surprises us.

I am learning biology everyday with some new facts . It's really unpredictable. Thanks for the extra knowledge ❤️

Thumbnail: "Do you have a ghost twin?" Me: "How'd they know I had a stillborn twin?"

So you're telling me fusion exists and I don't have to dance or wear ear rings for it

The amount of chills I got from the beginning omg, this is fascinating, thank you for teaching us all about chimerism! ❤️

I had to watch this video multiple time because the story, animation, and music are all experiences. Great experiences. 1:01 is my favorite part. The split of the person and the music is just an amazing pair.

Yes I do have a ghost twin actually she died in the womb and I've been watched over by her my entire life. yesterday I asked her if she could hold and squeeze my hand and I felt it it was so comforting to know that she listens to me because 4 months ago she threw my phone down the hallway and I asked her to not throw my phone again I'd prefer it if she chose the items that are not breakable since then she hasn't thrown stuff as hard as she did with my phone and they've all been non-breakable items. I used to see her as a child all the time and talk about the girl who looks like me at that age my mum hadn't told me about my twin and now I only occasionally see her for a split second out the corner of my eye but she's always there for me

The possibility of this makes me think I'm not alone. I was never alone. Thank you for sharing this info

That is so cool and amazing. I hope Ms. Keegan got the help she needed, though. Astounding animation as always; really great stuff.

Wait what!? I absorbed my twin... So my kids could actually be my nephews and nieces!?

Could this affect your mind at all? Such as both liking and disliking something, being extremely indecisive, or simply feeling like two people in one?

That's the beauty of science and mother nature.

This is fascinating and it made me think of what my Mom told me about my own twin who never made it to term. Whenever I didn't finish a meal growing up, our housekeeper used to say that I was saving the food for my twin.

Ted-ed: "(but not the way you think)" me: oh, so not chimerism? Ted-ed: "chimerism" ... 💨

Biology is a world in itself. This is what fascinates me to become a researcher in the future.

I had the same experience as Keegan's sons, I'm my 'aunts' son ^^' we found this out after my mother had a hysterectomy and they found part of the 'twin'. We later confirmed it through 23&me x)

One of the most interesting topics I've ever seen on TED Also, love the animation!!

That is so cool. Also the way the animations flowed in this video was enchanting

It’s so cool because you can look at one of her sons and they look like what her sister could’ve looked like.

why is nobody talking about how beautiful these visuals are?

The animation is superb ❤️

I was a little spooked when I saw this because my twin wasn't born. I used to tell everyone when I was a kid but it was dismissed as a joke and I only remembered it recently. My therapist said it was actually common and that sometimes the twin who was born mourns the absence of the other, which is my case. I thought this video was going to talk about that and felt a little scared but now I see it mentioned this in a more scientific take. It was interesting to know. I hope I have something of my sibling to carry along with me, even if it's a single cell.

I love the sound of this video! The background music and the sound effects! It's so relaxing! And with the comination of the video it was spectacular! Please do more videos like that!

Everybody’s talking about chimerism, I’m just loving the music. I wish I could listen to it by itself

This was a fascinating watch. I was truly in awe at such a neat find, but the animation wonderfully pulled everything together like an extra gift to the viewers.

‘As many of you know, I ate my twin sister in utero. So on my birthday, I try to remember I'm a winner. This one's for you, Connie.’ - Señor Chang

I could possibly be a chimera because I absorbed my twin in utero. Mom didn't tell me until I was 13 but I always felt like I was missing someone and felt so terribly alone even before I understood what loneliness was.

1:55 That's literally a rejuvenation process, so it is possible after all

let's take a moment to appreciate the beautiful animation❤️

The animation is absolutely stunning!! Especially love the animation of the progression from zygote to foetus!

There is an episode in House MD on chimerism. Nice work TedEd

So, when I am talking to my self . . . . . . .

The animation in this one is drop dead gorgeous.

We can all agree that this is fascinating, but the animation is also superb. Kudos Ted-Ed!

This changes everything . Why havent they introduced this in the books ??? 😳😳😳 Fascinating