I don't believe there are any missing chapters? i counted them and there is all 72,
they may be old missing warnings and the chapters were updated but the missing section wasnt.
however i may be wrong.
@GrimThoughts
I see what you mean, but i believe that Japanese values to tend to focus more on people getting a job, moving out, and getting a reliable source of income, essentially theres a lot larger stress on people becoming independent and self sufficient, so i guess its normal for her...