Take the key in the parent node that splits the left sibling and the leaf, the split key, and insert it into the leaf.

In acute and typical diseases, the fewer your remedies the better: but beyond this range, you can hardly have too many. It is here that the mere specificker, the mere organopathist fails; while the full method of Hahnemann wins victories which are a continual source of delight.

Pardon me, Proteus, all I can is nothing / To her, whose worth makes other worthies nothing; / She is alone.

J. Sedgewick (1840) Timon, but not of Athens, page 200: “Always spanielling at the heels of power, the mitred Dignitaries displayed, from first to last, the most rancorous hostility against her.”