To consider the policy event of a gift tax reduction earmarked for housing acquisition, the interdependence of parental gifts and children's housing investments is modeled, considering an informal care issue behind such decision making. The empirical results, which use a sample of households who purchased a house in Japan, demonstrate that such a tax cut would appear to have the following limited effects on boosting housing investment in equilibrium. First, even though transfers are encouraged, they consequently reduce housing investment because the housing investment function is negatively related to gifts. Second, increments in housing investment are further discouraged because the slopes of the gift and housing investment functions have opposite signs.