Outside of smoking and drinking, which are both legal, do you have undeniable proof to drug use that could put her in jail? If there isn't undeniable proof of abuse or neglect, you cannot violate your daughter's constituntional right to raise her child the way she chooses. She could suffer from all kinds of personality disorders and it wouldn't matter unless she is clearly without a doubt abusing or neglecting her son. This can't be your opinion that it is abuse. It must be fact.