本論文建構一個生小孩與養寵物為內生的經濟成長模型,研究小孩、寵物與經濟成長的關係。本文發現當生育率與寵物的固定替代彈性相對兩者的跨期替代彈性較大時,兩者將呈現負向關係;反之,若固定替代彈性相對較小,兩者呈現正向關係。而生育率和寵物對經濟成長的影響,取決於以外生變數的變動、固定替代彈性以及跨期替代彈性的相對大小而定。 We construct an endogenous growth model with endogenous fertility rate and number of pets to examine the relationship among children, pets and economic growth. We find that there is a negative (positive) relationship between children and pets when the constant elasticity of substitution between them is larger (smaller) than the intertemporal elasticity of substitution. The relationships between economic growth and fertility rate/pets depend on the variation from exogenous variables, constant elasticity of substitution, and intertemporal elasticity of substitution.