Not my idea originally or nor do i take credit for it. It brings up a important question of where is Naruto's grandparents.
Here is the original post that i found on another forum while i was searching to see if there was any spoiler out.
This is a theory i have been thinking about for a long time, but never really got around to posting it because it wasn't top of my list on the theories/threads that i wanted to post. Anyway i think its pretty apparent from the hints in the manga that Tsunade and Dan are Minato's mother/father. The reason i think this is true is because there are just so many hints shown in the manga and Data-book thats its almost undeniable. So i'll try and keep this short and post them in a list
1-Tsunade and Minato have the same exact blood type(B).
2-Dan and Minato graduated the Academy at the Same time(When they were 10) *not literally the SAME year
3-Tsunade and Minato Share the Same Hair Color(Blond)
4-Minato and Dan are around the same height and weight as each other(they are only different by a 3-4 in both categories)
5-Naruto and Nawaki(tsunade's brother) look nearly identical. Shows possibly a family resemblance
6-Its interesting that naruto always calls Tsunade Grandma Tsunade, which would be very ironic on kishi's part if it was true
Now that the basic comparisons are over here's the real big evidance
5-Madara suggest that the Hokage line has been kept in the Senju clan for years. When he talks about this their is a picture of the hokage mountain and it shows the fourth hokage's head on it. This implies that the Hokage position was still held by the Senju even during the fourth Hokage's time, which inturn implies that the fourth hokage is a Senju.
Where else would he get the blood from the Senju clan then Tsunade.
6-Tsunade passes down the hokage necklace to naruto which was set to stay in Tsunade's family and passed down in their family since the first hokage. Since there is a big deal made out of the necklace i think this implies that Naruto might be in Tsunade's family.
7-Yamato remarks about naruto's Chakra being special because he is able to hold off the power of the 4-tails w/o dieing. This might be because naruto is related to the Senju clan and thus his chakra has the same qualities as Shodai which helps to protect him from the kyuubi chakra
8-There is a great amount of symbolism between Shodai-Naruto and Sasuke-Madara. They stood on that statues of each other at the valley of the end(Naruto on Shodai's and Sasuke on Madara's). Many people thought this implied that Shodai is like naruto and sasuke is like Madara. But Sasuke is actually and Uchiha so i don't see why this wouldn't also imply that naruto is a Senju.
9-And i think this is the biggest telling piece of information eventhough some people might read the dialog differently then i did. Now remember the chapter where Jiriaya tells Tsunade that he is going to Ame to look for AL and they have Sake. Well when their discussion turns to minato alot of things bother me about the way Jiriaya talks to Tsunade.
...................continues on if you look at the link.
To be honest its a thoughtful question since it brings up many question and answers.
Like who are indeed Narutos Grandparents from mothers and fathers side. Its astonishing that no one brought that up. Narutos mother might be dead and father dead confirmed but where are his grandparents.
Fourth Hokage died young said best so his parents must be around about 40ish minus and plus 3 years. Because i can guess but Minato is around about 20 years old. Now Minato's parents and Narutos mother's parents would be later 50's. Why did they not be there for Naruto?
So to me Tsunade kind of fills the role since as the person said:
-Tsunade had Minato, "baby", and left him for adption so why he doesn't have the family name, although Tsunade doesn't carry the Senju clan name in the first place.
-Minatos father could be Dan, as Tsunade greatly cares and loves him and we don't really know what colour his hair his, or i think that is. We see it in the anime but anime could have twisted it because even they did not know what colour it was since Kishi doesn't work really closely with the animators i guess like Tite-Bleach creater does.
-Minato could have been adopted by Namikaze familly, and Tsunade left the villiage although time to time visited or be labelled as missing-nin.
-So, does Minato know about his parents? If so, why did he not leave his child to their care before death if he had time to make a request that Naruto should be seen as a hero?
-Lets not have deaths again that they died early, as well as Narutos mothers parents.
-I can also guess that when Minato died, Tsunade and not even Jiraiya was present in the village and also she was so shocked of his news of death she never returned to the village or somthing like that. Also Naruto was kept a secret in the first place so she might have not even known until Jiraiya informed her at which some else was looking after him when Naruto was a baby like a foster mother thing.
Points for the thoery:
-Minato has a massive chakra pool, to pull of S-class Jutsu's like that and only Senju clan members were said to have massive chakra pool.
-It was said Hokage line runs through the Senju clan by your truly Madara who we know has been alive since the first hokage, so Minato is one as well.
Its like Jiraiya said: "if he have been my kid, i would have bragged about him always
". So we can take it as he knows Minatos parents
and also they are alive yet they don't brag about him
. You can't brag if your not alive and since Jiraiya sounds like Minatos parent (who ever they are) should be very proud, they are indicated to be alive or one of the parents at least. Since Tsunade is the only one present and who is never known to brag, then why do we get the feel its her. She looks down (sad) with her head down at the moment and unhappy soon as Minato got mentioned.
Does she feel responsible for Minato anyways? Why be sad about Minato who she might have never known closely since she has not been in the village for a long time after Dan's death. Why is she lost in her thoughts if you look at her face in:http://www.onemanga.com/Naruto/367/10/
. I don't see Jiraiya making the sad expression and what Jiraiya said afterward in the next page sounds like he is trying to cheer Tsunade up.
I mean Minato could be blood related only and so on but its strange thou.
The only thing that goes against this theory is:
A) Orochimaru did not offer to Tsunade, that he would bring back Minato alive which means:
-Tsunade does not care for him, and how could for a son she never known on a personal level
-Orochimaru hated Minato too much because he took his Hokage position
-Orochimaru doesn't know, which is likely since he was more or less mad with Immortality to have noticed who gets born or not.
B) Tsunade never calls Minato on a personal level. Calls him either Fourth Hokage same as her grandfather "first hokage" or full name Namikaze Minato. A mother never does that but is it because she feels detached and guilt for not being there for him? Afterall she even explains when you become hokage you have to call them properly and no first names.
Her own words after she took the role of 5th hokage.
Who knows and who cares if Minato is indeed son of Tsunade and Dan beause in the end question remains:
Narutos parents might be dead but where were his grandparents who are never mentioned and did not even bother to look after him from such troubled childhood?