I analyze strategic interaction between adult siblings in the provision of care to an elderly parent by estimating a dynamic discrete-choice game in which siblings make location, work and care choices. I find that the opportunity for strategic play exacerbates gender differences in caring responsibilities as sons in particular strategically shirk providing care as they believe their sibling is relatively likely to provide care in their absence. Counterfactual experiments show that if siblings instead took care, location and work choices independently then the gender care gap would be around 14% smaller. Also, I find that unobserved preference differences between sons and daughters are far more important in driving the gender care gap than observed differences in wages.