The children were found around 9pm.
The suspect is the children's mother, Marisol Duarte. She has supervised visitation rights, but it's her mother who cares for the children.
Marisol was last seen in Galveston, picking up Tiana at Parker Elementary School at 69th and Jones Drive. Makayla was picked up at Busy Body Day Care at 6904 Lasker Drive at 8am Thursday.
They are believed to be driving a light, olive Green, 2011 Mitsubishi Galant. The license plate number is unknown at this time.
Authorities say Marisol has been in touch with a CPS case worker since she took the kids, but when she didn't return them when she said she would, CPS reached out to the Galveston Police Department, which then issued the Amber Alert.
Police say the mother lost custody of the girls and has a history of drug use and mental health issues. The children are believed to be in danger.
Tiana was wearing a red polo shirt and khaki capris, and Makayla was wearing a red striped shirt and black pants.
Anyone with information regarding the suspect or children is asked to immediately contact Sgt R. Orozco or Ofc. Campos with the Galveston Police Department at 409-765-3702.
Take ABC13 with you!
Download our free apps for iPhone, iPad, Android and Blackberry devices