See a trust attorney.
They may be able to structure a trust that eventually leaves the real estate to your granchild, and provides Mom a life estate interest only, and a place to live and bring your grandchild on her times of possession. The trust can have some funds allocated for property tax payment and property preservation, so as to keep the property in the hands of the trust until your grandchild eventually inherits it. Disbursements from the trust to daughter (how much and whether to ever touch principal, rather than disburse earnings-only to your daughter is a fiscal management decision to address during estate planning) can indeed count as income to her and be partially offset to pay CS. The trust could potentially preserve the principal for eventual inheritance by granddaughter, while payments from it could help daughter in paying CS and having a roof over her head to bring her child home to.
Do NOT have daughter as trustee. Use a fiduciary, perhaps a bank, or reliable third party relative, to manage the trust.
Adoptive parents ARE "real" parents. Sharing genes is not what makes you a "parent"!