Disclaimer: I don't own Naruto, thus I don't own Kakashi, or the Yondaime...
Tags
When a child graduates from Academy, they give him or her a hitai-ate. All the children are ecstatic, showing off their shiny new headbands. A week later, once the list of genin has been finalized, a second symbol of graduation comes.
That day, the jounin sensei has a brown paper envelope in his hand when he meets his team. It jingles a little as he walks, the distinctive rubbing of metal on paper mixes with the sound of metal against metal.
Kakashi is short for his age, and when Minato hangs the chain around his neck, the tags hang below his bellybutton. The tall, yellow-haired man laughs. "We'll get that shortened, Kakashi-kun."
The five-year-old fingers the metal tags. Name, serial number, blood type. Hatake Kakashi, 021405, O. "Why are there two?" he asks innocently. "They say the same thing."
Minato's eyes flicker. Then he drags his suddenly serious blue gaze back. "If you die, Kakashi-kun, and your team can't bring you home, they leave one tag with your body. That way, a later team can identify it."
Kakashi's little head nods. "That makes sense." He doesn't sound bothered. The rounded rectangles jingle.
"But you won't need that," Minato says, and prays for it to be true. Not yet, anyways, not before you're tall enough to wear them.
Kakashi smiles under his mask, tilting them forward and back to catch the light. "They're shiny."
And Minato forces himself to smile back, his own pair of metal tags burning into his chest. "Sure, Kashi-kun. Sure."