Kiana Davis-Webb, 31, also known as Kiana Janelle Davis, was arrested Feb. 18 after she admitted to police that she had consumed Vicodin and alcohol before operating a car with Daphne in the back seat, according to records.
Oakland police Officer Alonzo Weatherly said in a report filed in court that a pedestrian called police "out of concern" for Daphne after seeing Davis-Webb passed out behind the wheel of her car, with the child inside.
Weatherly said Davis-Webb "admitted taking Vicodin/alcohol prior to driving" and police recovered Vicodin from her purse when they searched her.
Davis-Webb "apparently didn't have a prescription for it," Weatherly said.
The mother pleaded no contest to misdemeanor child endangerment and misdemeanor possession of a controlled substance April 10.
Alameda County Superior Court Judge Carol Brosnahan placed her on three years' probation, issued a protective order mandating that she do no harm to Daphne, referred her to a domestic violence/anger management program and ordered her to attend 26 parenting classes.
Brosnahan also ordered Davis-Webb to destroy all her Vicodin and pay a $350 fine.
Daphne was reported missing a week ago today by her father, 49-year-old John Anthony Webb of Oakland.
Webb told police Daphne was abducted by a stranger shortly after 11 a.m. last Wednesday while she sat in a parked car with his 87-year-old mother while he went inside the Gazza Supermarket at 7838 International Blvd.
Oakland police arrested Webb on suspicion of felony child endangerment later that day because they were concerned that he left Daphne in the care of his mother, as she suffers from dementia, police spokeswoman Johnna Watson said.
However, Webb was released from custody Friday after the Alameda County District Attorney's Office said it's declining to file charges against Webb.
According to Watson, Daphne lives with her father and grandmother at a home in the 800 block of Greenridge Drive, off Keller Avenue, in the Oak Knoll area of northeast Oakland. Davis-Webb lives at another location.
Davis-Webb appeared with her father and about 30 other family members and supporters at a news conference outside Oakland police headquarters Tuesday afternoon at which it was announced that a website has been set up to serve as a central information hub in the search for Daphne.
Davis-Webb didn't speak at the event. Her father, Kevin Davis, said she doesn't want to say anything because "she's too emotional for that."
Oakland police don't consider Davis-Webb a suspect in Daphne's disappearance, Watson said.
John Webb didn't attend the news conference.
A candlelight prayer vigil for Daphne was held Wednesday evening at 79th Avenue and International Boulevard, near the location from which she was reported missing. At that event Davis-Webb sang a song to her missing child and answered the criticism that she wasn't crying enough during a recent interview.
"I'm not worried about people seeing me cry enough. You have no idea how heart breaking this is. How devastating it is," said Kiana-Davis. "There's no way to express how you feel when you're child is missing and you don't know where they are and you can't find them and you can't hug them."
John stood apart from his wife throughout the vigil.
ABC7 News contributed to this report.