Genesis 42:32

We [be] twelve brethren, sons of our father
All brethren by the father's side, though not by the mother's, and by one father; they had been twelve, and were so now, though they knew it not, supposing that one was dead, as is next observed: one [is] not;
is not alive, but dead; the Targum of Jonathan is,

``what is become of one we know not''