In this article, the author discusses her research into the development of counting in pre-school children. Her research involved a small-scale case study with a personal flavour--the children in the study were her twin daughters (called Emily and Alice for the purpose of the research). Observations of their mathematical development began at 18 months and continued through to five years plus. As part of the research, the author identified 50 different elements involved in the development of counting and arranged these into a framework. She then mapped the development of the two children onto this framework. This revealed significant differences between the children; differences that have implications for early mathematics and which the author explores in this article.