Sometimes, the apple falls from the tree, then rolls down a long, long hill. Or it gets carried off by a squirrel to an entirely different yard.

Z is almost three. Today, she asked for an M&M, so I told her if she peed in the potty, she could have one. She ran off to the bathroom, sat down on her potty, and tinkled. I rewarded her with two M&M's, slapped some Elmo underwear on her, and poured her a glass of juice. Then, every 15 minutes, I asked if she needed to go potty. An hour later, after repeatedly denying any need to go potty, she pooped and peed in her underwear.

This is a far cry from her self-potty-trained-at 23-months mother.

Help me.