Ultra-thin fashion dolls may represent a risk factor for thin-ideal internalisation and body dissatisfaction amongst young girls. We asked thirty one 5- to 9-year-old girls to engage in interactive play with commercially available dolls which were either ultra-thin (Barbie and Monster High) or represented a putative realistic childlike shape (Lottie and Dora) and to indicate their perceived own-body size and ideal body size on an interactive computer task both before and after play. There was a significant interaction between testing phase and doll group such that playing with the ultra-thin dolls led to the girls’ ‘ideal self’ becoming thinner. A further 46 girls played with the ultra-thin dolls and then played with either the same dolls again, the realistic childlike dolls, or with cars. Initial play with the ultra-thin dolls again produced a drop in perceived ideal own body size; however, no group showed any significant change in their body ideals during the additional play phase. These data indicate the potential benefit of dolls representing a realistic child body mass to young girls’ body satisfaction and do not support the hypothesis that the negative impacts of ultra-thin dolls can be directly countered by other toys.