What if Minato and Kushina gave birth to a twin naming them Naruto and Menma. When the Kyuubi attack Konoha Minato seals the Kyuubi to his sons by splitting the Kyuubi into Yin and Yang. Yang for Naruto and Yin for Menma.
We already knows Naruto's Personality, Appearance, Skill, and Abilities.
Menma takes more after his father, as opposed to Naruto, who was stated to inherit his mother's personality traits. Menma is calm, collected, talking only when he feels it serves a purpose. In contrast to Naruto, who is usually childish and cheerful, Menma is mature and very serious. He is also shown with a sharp wit, carefully thinking before acting and able to see the underlying nature of the situation at hand.
Menma looks virtually identical to Naruto, though his blond hair is longer and more shaggy-looking in style with jaw-length bangs framing either side of his face, similar to his father's.
As an Uzumaki descendant, Menma has an especially strong life-force, granting him tremendous reserves of chakra and vitality. Derived from these traits are also an incredible healing factor and longevity.
(He's basically Menma Namikazi from Tenten's Infinite Tsukuyomi dream)