She could not go from claiming the state failed her for not educating her children properly, something they more than likely were, to claiming they taught them too early or too much.

She is completely irresponsible for not knowing what her daughters were doing, and at least to the 16 year old, who is legally entitled to have sex (presuming it is a story from the UK), she should have talked to her about contraceptives and such, and if she knew the others were in sexual relationships she should have tried to stop them, or at least talk to them about contraceptives too.