Stable isotope analysis is firmly established as a method for the investigation of past population mobility. The distinction between local and non-local individuals within a cemetery population relies on identifying an individual’s place of childhood residence through the analysis of strontium and oxygen isotopes present in human tooth enamel. Traditionally, studies investigating mobility focus on the analysis of a single tooth. More recently, however, it has become apparent that in order to investigate the mobility of an individual during childhood—and thus to consider the importance of children in the migration process—it is necessary to analyse a series of teeth which form at different stages during the early years of life. This chapter will consider the potential of—and challenges surrounding—this scientific approach to the investigation of childhood mobility in the past.