Note : Hospitalized incest daughter 's condition is grave but stable , police say . The 73-year-old Austrian began building the dungeon as part of an addition to his home that year , and simply added the hidden space -- which was not recorded in any building plans -- Polzer said . Fritzl beat and raped her , also threatened her children , police say . Wife of Josef ##s was too scared to question him , her sister says . Fritzl 's wife insisted on keeping family healthy , according to her sister .
Note : Hospitalized incest daughter 's condition is grave but stable , police say . Fritzl beat and raped her , also threatened her children , police say . Wife of Josef ##s was too scared to question him , her sister says . Fritzl 's wife insisted on keeping family healthy , according to her sister .