“…As Ettner (1995) points out, economic research had previously been more interested in child care and its effect on female labor supply than in elderly parent care, which plays an increasingly important role with population aging. In more recent years, the literature on this issue proliferated from Europe (Carmichael and Charles, 1998;Carmichael and Charles, 2003;Crespo, 2006;Heitmueller, 2007;Heitmueller and Inglis, 2007;Casado et al, 2007;Bolin et al, 2008).…”