My step-daughter is 14. Her mother tested positive for every controlled substance out there on a drug test, is allowing boys to spend the night in my step-daughter's room (with the door shut) and there have been rumors that my step-daughter's mother has taken her in for abortions. The abortion thing is hearsay, however, so I cannot attest to the validity of this claim. 

Regardless, her mother is using drugs and is often found on the floor with my step-daughter at her side trying to take care of her. 

Here is my question, if we are fortunate enough to win this custody battle, I want to forego her mother paying child support, and have the court allocte that money to her mother's counseling and rehab. My step-daughter needs her mother to be healthy so she can be a positive presence in her life. However, I also recognize that: (1) I don't know that the court would be able to specify where she spends her money, and (2) if the court cannot make that demand, we could simply be enabling her by not requiring her to financially support her daughter while she's with us. 

Would you require her mother to pay child support to demonstrate some responsibility, or would you ask the court to (if possible) allocate that money to counseling for her mother and drug rehab? 

Thank you in advance.