What counts as counterfactual thinking in children?

The first studies on the development of counterfactual thinking focussed on one question: whether there was a shift in children's speculation about what might have been at 3-4 years of age. Since then findings from a diversity of tasks have suggested that children's abilities develop somewhat earlier (German & Nichols, 2003; Harris, 1997), later (Beck et al., 2006; Rafetseder, Cristi-Vargas, & Perner, 2010), or that the emergence of adult-like counterfactual thinking (e.g. shown by regret) might be separate from the basic reasoning abilities (e.g. Guttentag & Ferrell, 2004; Weisberg & Beck, 2010; 2012). I will explore which of the developmental data offer good evidence for counterfactual thinking and identify questions that remain.