Cherman does have some good suggestions.
As a ER Truma nurse i saw far to many daughters like yours being
brought in. It's heartbreaking but i to agree with your tough love.
Hospitals have social worker's who can intervene,perhaps one can
help your son-in-law. No child deserves that,i wish you all the luck
in the world. Many hugs For the hard times.. And many
blessings for the wee one.