In this theory, I’m going to tell you who the forgotten D is and why because of this person, Law might end up betraying the Straw Hats.
As an extension, I will talk about another D, as well as another possible D.
Also, on a side note, Law will not betray the Straw Hats for Kaido. Even if it looks like Law has completely betrayed the Straw Hats for Kaido, Oda will find a way to make Law look like he did “what he did” to help the Straw Hats. This is because Law has nothing to gain from Kaido.
Here you can watch the video version of the theory:
Now coming to the forgotten D, this is a character that has already been introduced in the story, but hardly anyone talks about this character. But I feel this D is more important than what Oda has led us to believe. Which is why he has subtly made us forget about this character.
Now cutting right to the chase, who is the forgotten D?
The answer to that question is Lammy.
Now you guys might be thinking “Who the hell is Lammy?”
Her full name is Trafalgar D Water Lammy. She is Law’s biological sister. Since Law is a D, she is automatically a D. Also, since Law is a D, one or both of his parents are Ds making them the other 2 Ds I mentioned earlier.
Now that I have told you Lammy is the forgotten D, the next thing that you guys will be thinking is “How will dead characters make Law betray the Straw Hats?”
Well, we only saw dead bodies of Law’s parents, not Law’s sister. We last saw Lammy, it was in the hospital where Law hid her, and when he came back to the hospital, he saw the hospital burning. Because of this Law assumed she died in the flames and so did we.
So Lammy was last seen in the closet of a hospital, which was burned to the ground. Even if she somehow escaped from the hospital before it burned down, there was no way she could have gone far because she was really sick and could barely run. Thus, making it impossible for her to run away from the guards, who were torching everything on sight. This makes it nearly impossible for Lammy to have survived. I think Oda has really gotten out of his way in making us think she died. But since Oda wants to make us believe she died, I think she survived.
So why do I think Lammy is alive?
Well if this was some other anime where presumed “dead” characters do not come back alive, then we could say that she died. But this is One Piece, and Oda will not kill characters just like that. Oda did the same for Sabo, Pagaya and Pell. They survived even when the chances for survival for them was nearly 0. Even for the Going Merry a ship, Oda did the same. So, until a person’s dead body is shown, we cannot assume that the character is dead. Same goes for Pedro, Pound etc, they might have survived their deaths, we never know. This is like Schrodinger’s cat until the character’s dead body is shown, we need to be open to the possibility that the character is both alive and dead at the same time.
Therefore, even if there is an insignificantly small chance for her to survive, since we have not seen her dead body and adding to the fact that she is a D, I feel she survived.
Also since Law lost everything dear to him that day and saw so many atrocities like his parent’s dead bodies, his countrymen slaughtered in front of him, his city burning to the ground etc, him finding out his sister survived will not make his backstory any better.
In Fact, if Law finds out that his sister is alive, we might see a new Law, a Law we have not seen so far, a Law filled with disbelief and hope. Thus, allowing Oda to take Law’s character arc in a new unprecedented way.
So, how could Lammy have survived?
Well to answer this question, there could be multiple ways she could have survived. She just like Law, could have escaped through the dead bodies. Or like Aokiji taking pity on Robin and allowing her to escape, some guard could have taken pity on her and few kids to allow them to escape. Or maybe she was found by someone in the hospital and took her safety.etc. But escaping the city was just half the problem, the bigger issue was after that. Unlike Law who had a few years left to live, she was too sick and had just a few months left. Further making matters worse was that no doctor would even look at her, let alone cure her.
So, unless she found herself a doctor who was willing and capable of curing her or a devil fruit that could save her, all while avoiding world government along the way and in just few months, her escaping the city was pointless.
But if there was someone who could cure her and was taken there directly without the need of being hidden from the world government, she could have survived.
I mean what if the guards or someone higher up took her as a test subject, to find the cure to her disease, to someone who could actually cure her, then I think she could have survived.
The main reason they would do that is if anyone important got infected with that disease, like the nobles of Flevance (Law’s country) they need to find a way to cure it.
For that, they needed test subjects. There is a panel where we see that a Sister was told that the guards will not kill children. She told Law to bring his sister so that they could escape. But when Law went back to the hospital, it was in flames and when Law came back to the Sister, she and all his classmates were dead. So this begs the question, why did Oda show us this panel? Is it just because he wanted to show that even children were not spared? It just does not make sense. I think the main reason why Oda showed this panel was because he wanted to foreshadow that the Guards took some children as test subjects. And because there were enough they killed Law’s classmates. And I think Lammy was one of the test subjects chosen.
And the person she was taken to as a test subject was Vegapunk.
Well, who else who among the world government we know is a person capable of curing diseases which as of yet do not have any cures. This is further evidenced by the fact that Tashigi did the same to the kids from Punk Hazard.
Which is why I feel she was taken to Vegapunk and he has been slowly extending her life but was still unable to cure her.
Now that being said when, why and how will Law betray Luffy and the Straw Hats?
As of this theory, the present chapter is 964. In the last few chapters, Oda has been excessively hinting that Law will betray the Straw Hats. I feel that might actually be the case. But the difference between what Oda wants us to believe and what I have in this theory is that Law will not betray the Straw Hats for Kaido, but rather for the world government.
So, from chapter 964 till Kaido is beaten, Law will not betray the Straw Hats, even if he looks like he has joined Kaido, Law’s end goal will be to defeat Kaido. And to achieve that, he might even join Kaido and secretly help the Straw Hats in taking down Kaido from the inside.
But once Kaido is defeated is when I feel Law will betray the Straw Hats. Why?
This is because Law has assured Luffy that he will not betray Straw Hats. And way back in the Punk Hazard arc in chapter 668 Robin even told that alliances come with betrayal. So both of these can be come true if at the very end of the arc after Kaidou is beaten, Law betrays Luffy to the world government. Since Luffy has beaten Kaido, the alliance is over and Law has not not betrayed the Straw Hats during his alliance, and Robin foreshadowing also has come true because the alliance has ended with a betrayal.
Also Luffy and other Supernovas are fighting 2 Yonkos and the possible inclusion of Blackbeard as well. Blackbeard might come at the end to kill the Kaido and take his Devil Fruit.
So once the Yonkos are taken down by Luffy, the Marines and World Government, who wouldn’t dare go against Kaido will suddenly find a golden opportunity to kill two birds with one stone.
They will have 2 Yonkos less to deal with and if they can take credit for defeating them, they will gain a lot of public support which they lost because of Fujitora and Doflamingo. But the world government will want to capture Luffy, who now would have beaten Kaidou.
Since CP0 are also there, they would be worried that Luffy is too strong and they would rope in Law to capture him.
So, how will the World Government do it?
Well, Orochi demanded Vegapunk at the start of the Wano arc for him to continue to give the world government with the weapons they need. Fearing Kaido, I think the CP0 will comply and we will see Vegapunk introduced in Wano.
Along with him, I feel we will see quite a few important characters like Smoker, Tashigi, a few members of CP0, maybe an admiral like Fujitora who has promised Luffy and Law’s head to Sakazuki will also come. And finally along with Vegapunk Lammy will be introduced as Vegapunk’s assistant.
I think Smoker and Luffy will do their own thing, so will Zoro and Tashigi. The CP0, on the other hand, will talk to Law and make a deal with him.
The deal will be Luffy in exchange for Lammy.
Law I feel will be shocked at first to find out Lammy is alive and he will reluctantly agree to CP0’s demands.
After the battle against Kaido, when Luffy is really weak Law will sell out Luffy to the CP0. And they will give Lammy to him.
Also on a side note, Law might have been freed in the prison where he was imprisoned by CP0.
But without Vegapunk, Lammy will not have much time to live. Seeing Lammy in her deathbed, Law will perform the Perennial Youth Operation and save her by sacrificing himself.
Why would Law sacrifice himself? Well, he is her older brother and it is his duty to save her. Apart from that obvious reason, Law himself said the disease cannot be cured because of this if she gets older, she will die. To prevent the disease from spreading further and cure her to the best he can, he will perform the perennial youth surgery on her.
With Law dead, I think she will follow in the footsteps of Law and lead the Heart Pirates.
Then to get revenge against the world government, she might join the Straw Hats in an attempt to rescue Luffy who will be captured by the world government. And there she might defeat the CP0 to avenge her brother.
Further, Doflamingo mentioned that to use national treasure in Mary Geoise, one must be the recipient of the eternal youth surgery. So if Law performs the surgery on her, she might be able to use it. This gives her one more purpose in the story and also tie in that thread opened by Oda.
After Mary Geoise, she might join the fleet or go in her own way forming a stronger crew whom we might see at the end of the story.
Further being a D and also being around the same age as Luffy, she might be Luffy’s love interest. I feel her chances of being Luffy’s love interest is higher than Boa or Nami.
So I think we finally found the mother of Luffy’s child in Trafalgar D Water Lammy.
*Theory by Ashura The Demon