Genesis 43:7

לנו ולמולדתנו CONCERNING OURSELVES AND CONCERNING OUR KINDRED — concerning our families. A Midrashic comment based upon the meaning of מולדת, “birth” — He asked of us concerning the circumstances of our birth — is: he could even tell us of what kind of wood our cradles were made (Genesis Rabbah 91:10). ונגד לו AND WE TOLD HIM that we had a father and a brother. על פי הדברים האלה ACCORDING TO THE TENOR OF THESE WORDS — we were forced to tell him according to the tenor of the questions he put to us. כי יאמר THAT HE WOULD SAY — The word כי is used here in the sense of אשר “that”. The word כי may be used in the sense of אם and אם may be used in the sense of אשר; therefore this (i.e. אשר) is one of the four meanings in which כי, according to the Rabbis, is used, viz., אם (Rosh Hashanah 3a), for the word כי here has the same meaning as אם, as in (24:33) עד אם דברתי דברי “until that I have spoken my words” (where אם is the same as כי or אשר).

וַיֹּאמְר֡וּ שָׁא֣וֹל שָֽׁאַל־הָ֠אִ֠ישׁ לָ֣נוּ וּלְמֽוֹלַדְתֵּ֜נוּ לֵאמֹ֗ר הַע֨וֹד אֲבִיכֶ֥ם חַי֙ הֲיֵ֣שׁ לָכֶ֣ם אָ֔ח וַנַּ֨גֶּד־ל֔וֹ עַל־פִּ֖י הַדְּבָרִ֣ים הָאֵ֑לֶּה הֲיָד֣וֹעַ נֵדַ֔ע כִּ֣י יֹאמַ֔ר הוֹרִ֖ידוּ אֶת־אֲחִיכֶֽם׃

And they said, The man asked us particularly of our state, and of our kindred, saying, Is your father yet alive? have you another brother? and we told him according to the tenor of these words: could we possibly know that he would say, Bring your brother down?