This double negative emphasizes that the lamb was the only thing that the poor man owned. This is probably an exaggeration that means that the man loved this lamb more than anything else he owned. Alternate translation: "the only thing the poor man had was one little ewe lamb ... raised" or "the poor man had a little ewe lamb ... raised, and which he loved more than anything else he owned" (See: [[rc://en/ta/man/jit/figs-doublenegatives]])
This refers to the closeness of this man and his little lamb. Alternate translation: "he loved it as much as if it were one of his daughters" (See: [[rc://en/ta/man/jit/figs-simile]])