frau fritzl already had seven children and now she has to bring up grandchildren, as well. le. >> incredibly, over the 24 years elisabeth was in captivity, there were more than 100 tenants renting rooms in the fritzl house right above elisabeth's prison. none suspected. >> translator: in hindsight, you can always claim that you heard something, like knocking, but that simply isn't the case. i can't recall ever hearing knocking or anything at all. and if i heard something, what could i have done? it could have been children playing. you don't know. >> after the first child was abandoned in 1992, social services paid some 20 visits to the house. with fritzl's rape conviction erased from his records, they had no reason to be suspicious. in fact, social workers left, impressed by his wife, rosemarie. >> the grandmother took loving care of the children, lisa, monika, and alexander. these three children were very well brought up. they were doing very well at school. they were integrated in the community. and the notes and records about all the meetings with the grandmother frau fr