Hi, it’s Junko from Japan! Is YORIICHI related to TANJIRO in Demon Slayer? No, he isn’t.
Is Tanjiro a Descendant of Yoriichi?
Yoriichi looks like Tanjiro, but they don’t have any blood relation. Originally, Yoriichi lost his wife and a baby inside her belly. He remained single for the rest of his life, and his lineage didn’t continue.
While Tanjiro may resemble Yoriichi with the red eyes and the mark on his forehead, their bloodlines don’t (can’t) interwine.

For your information, Tokito Muichiro is a distant descendant of TSUGIKUNI MICHIKATSU, an older brother of Yoriichi. That means it’s Muichiro who is related to Yoriichi.
I think it’s Tanjiro’s father, KAMADO TANJURO, who resembles Yoriichi rather than Tanjiro. They both had a calm and moderate atmosphere. Also, Tanjuro was born with a red mark on his forehead and reached the transparent world.
The red mark is a symbol for the legitimate successor of the Sun Breathing. Though Tanjuro’s body was weak, it seems his soul and ability were very close to that of Yoriichi.
Is Tanjiro the Reincarnation of Yoriichi?
Then is Tanjiro the reincarnation of Yoriichi? I suppose not. It’s true that Tanjiro witnessed Yoriichi’s past. But that was a memory he inherited from his ancestor KAMADO SUMIYOSHI.
If Tanjiro was truly the reincarnation of Yoriichi, he must have seen it from Yoriichi’s view.
Who Is Yoriichi to Tanjiro and the Kamado Family?
To Tanjiro, Yoriichi is a friend of his ancestor. Yoriichi met Kamado Sumiyoshi and gave him two things.
One is the Sun Breathing technique and Sumiyoshi passed down it to his ancestor as the Hinokami Kagura (Dance of the Fire God). The other are earrings that were a keepsake from Yoriichi’s mother.
Sumiyoshi is an ancestor of Tanjiro who lived with his wife SUYAKO. When they were attacked by a demon in the mountains, it was Yoriichi who destroyed the demon and saved them.
Suyako was pregnant, and thanks to Yoriichi’s help in calling for a midwife, she successfully delivered a healthy baby.
So, Yoriichi is a lifesaver of the Kamado family. If he had not appeared, Tanjiro nor Nezuko might have not been born.
Two years later, Yoriichi visited them again and told his past to Sumiyoshi. Sumiyoshi felt sorry for him and promised to inherit his earrings and the Sun Breathing forms from his descendants.
In this way, the Hinokami Kagura and the earrings have been passed down to the oldest son of the Kamado family, and the latest (and the last) successor is Tanjiro.
Related Posts about Demon Slayer
Who Is Yoriichi? The Tragic Legend in Demon Slayer
What Does Yoriichi’s Sword Say in Japanese?
How Did YORIICHI DIE? The Death of the Legendary Swordsman
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