don't you know you've got the best of me? (смешанная)

"Oh, my poor old heart can't take this," Fred says, clutching his chest.
"You're thirteen," Hermione scoffs, rolling her eyes. "There's nothing old about you."
"I'm a twin. Combined we're twenty-six years old."
"That's still not old, and that's still not how it works."
*\
(or: the rewrite of the books where the twins befriend hermione early on. some things change, some things stay the same, some things... do a little bit of both.)