Nope. They are definitely not related. I've been keeping up with Naruto by reading the manga, and the author has not given any reason anywheres in the manga to even consider them being related. In fact, she's given every reason to think they are not related.
Konan calls Pein by the name Nagato in chapter 429 of the manga, which is the name of one of the orphans from the land of Rain that Jiraiya took on as a student... Naruto's parents are the Fourth Hokage (Minato Namikaze) and Kushina Uzumaki from the village hidden in the Whirlpool.
So as you can see, there is no way Pein and Naruto are related, cause Pein definitely isn't Naruto's father and he can't be Naruto's brother cause they are from different lands. There just isn't any way.
Konan calls Pein by the name Nagato in chapter 429 of the manga, which is the name of one of the orphans from the land of Rain that Jiraiya took on as a student... Naruto's parents are the Fourth Hokage (Minato Namikaze) and Kushina Uzumaki from the village hidden in the Whirlpool.
So as you can see, there is no way Pein and Naruto are related, cause Pein definitely isn't Naruto's father and he can't be Naruto's brother cause they are from different lands. There just isn't any way.
