Correct on the first guess, Phil! Fred had asked me for a French version of "Sister, I would like a word with you in private, if you don't mind..."
I actually added the "ette" on soeur, to make it more like a term of endearment, as in "little sister."
And the second sentence is, quite simply, "Shut up!"
Gotta run for today, so à demain tout le monde!