Luong Tammy Huynh, 29, is accused of kidnapping, child endangerment and vehicle theft.
Court documents reveal Huynh admitted to hearing and seeing a baby in a car she's accused of stealing early Sunday while the child's mother was unloading groceries at a Travel Inn motel.
A police officer found the two-year-old toddler in that abandoned car hours later in an office park.
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He was left strapped in his cars seat in a soiled diaper for 13 hours with no food or water.
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He is doing okay.
Huynh was assigned an attorney and is expected back in court Friday to enter a plea.