post natal depression can drag on for years so i dont think its right to say that if the child is at school it must be over. there is no specific time frame or exact recovery date for post natal depression so i think there is a fair chance it could go for this long. so i think its very wrong to say there is no chance of having post natal depression just because the child is at school.
Can I just say that if you speak about your own child like this then maybe 'IT' as you call your child wld be better off with a new family that wouldnt harshly punish he/she just because they are not achieving to YOUR high expectations.