had lessened. >> having been where she's been for so long, doing it and knowing your children aren't likely to get out of there, either. so the mixed blessing of having a child but knowing that child is also going to be a prisoner and that happening over and over again. i just can't imagine how she did not, how elizabeth did not shut down entirely and give up. >> in total, elizabeth gave birth to seven of her father's children. today, only six are alive. a twin died soon after birth. his tiny body incinerated by joseph fritzl most likely in the furnace. three others felix now 5, stefan now 18 and kirsten 19 were condemned to lead a life in captivity with their mother. but incredibly fritzl selected the middle three children for a life of freedom upstairs.