I’m Lost (But I Don’t Know Why)

He is mourning the loss of someone he never knew, doesn’t know, but it hurts all the same. He thinks back to the nunchucks, and the orange tape wrapped around them. The comic books hidden under the couch. The extra plate that he sets up everyday, has been for the past three weeks. The gap in their formation.
Missing, missing, missing, his mind chants, but he can’t know what. He’s lost, and can’t remember why.
~
There have always been four of them - Donatello, Raphael, himself and his father. Or at least, that’s what Leonardo had thought. But something is missing. They are mourning the loss of another they have never even known. They are lost. But why?
TLDR: a curse makes everyone forget Michelangelo. Leonardo knows there’s something missing, but he doesn’t know why.