Click in the Eyewitness News Story Window above to watch Eileen Frere's report from the scene.
One of the children, 10-month-old Alakahi Thompson, was there being treated for pneumonia.
The other two kids, ages 5 and 11, were visiting their sick sibling at the time of the abduction.
Police identified the mother as 33-year-old Ida Marybel Torres, a Latina who is 5 feet 4, 125 pounds, with brown hair and brown eyes. She does not have legal custody of the children and lives in Kentucky.
Torres took off in a silver 2008 Chrysler Sebring, license plate 6AHA682. Police believed she was headed back to Kentucky with the children.
If you have any information, call the Orange Police Department at (714) 744-7313 or (714) 744-7444.