Seeking Child Support Modification

I am trying to assist my son in Colorado with a child support modification and motion to enforce. My son pays his live-in girlfriend for day care for his two children of the marriage (they also have a son together) Will the court allow this amount to be included in the child support calculations? She was awarded an automobile in the separation agreement and was to take full responsibility of that auto. She has not obtained financing in her name nor changed the title. The financing is in his name and shows on his credit report.