Care, support for disabled sister

Dear Len & Rosie, I am the trustee of my recently deceased mother’s trust, which includes a special needs trust for my disabled sister, Judith, who is on Medi-Cal and Supplemental Security Income. Both before and after our mother’s death, my sister has rented a property owned by the trust. As trustee, can I pay off the mortgage on this property and turn it over to my sister while staying in compliance with the terms of the trust? -- Ben