Anne Wirtz / A 3 year old girl with complaints of bellyaches and watery diarrhea. She wants things her way. She is very meticulous and sees every ‘imperfection’, stain or crack. She has a tendency to be overly careful which reminds the mother of a 60 year old person. The need for autonomy, timidity, fear to make mistakes before mastering things, the need for order, the perspiration on face and nose, and her being “a daddy’s girl” led me to a Lanthanide (Stage 4) Cerium - Carbonicum. The very day after the remedy her stool was normal and Instead of ‘like a careful 60 year-old person’, she turned into a child. Keywords: Cerium carbonicum, diarrhea