Waco police arrested 43-year-old Noemi Constancio after finding her emaciated 2-year-old granddaughter in her home.
Officers received a request for a check welfare call Tuesday night and went to the home on Liveoak around 9:30 p.m.
When they got there, they say the home reeked of urine, clutter was everywhere, and filled with animals and roaches.
They say the 2-year-old girl was mumbling, using a walker to get around, and was skin and bones.
The officers called for an ambulance to take the little girl and her 6-month-old sister to the hospital.
Doctors examined both children and say the 2-year-old only weighs 13 pounds and suffers from Failure to Thrive and severe muscle wasting, as well as severe physical and mental delay. They say it took six months for the child to get to that level of neglect.
In contrast, the 6-month-old weighs 16 pounds.
Constancio, who is the legal guardian of the children, faces an Endangering the Welfare of a Child charge.