I imagine it to be the last in queue:
a line first, then a diagonal cross that leaves you
astonished, amazed
that later melts into a familiar line,
just a simple little line.
almost as knowing as a human, it
can hide very well;
its siblings s and c are mentioned frequently,
and display the same jingle, the same bell sound,
but still it remains
in hiding,
waiting
knowing not to come out too frequently,
so that it is never wasted, never exhausted, never dead
everlasting, infinite instead.
and it hides so well
that it is the only sister of the alphabet
that has not once
appeared in my words.
**Note: The answer is Z, in case you couldn't figure it out.