The girl's father left her in the car for a short time while he went into a store. When he came out, Daphne was gone. The girl's grandmother was in the vehicle but she suffers from dementia and hasn't been able to help.
Police arrested the father, Anthony Webb, and charged him felony child endangerment but later dropped those charges.
When asked why nobody saw the Anthony Webb with his daughter in the days leading up to her disappearance, there was no explanation.
"Well, right now we aren't taking any questions. We'll have to get to those answers later, OK? So, we just wanted to make the statement and get the information out," said Daphne grandfather Kevin Davis.
Law enforcement has ruled out the child's mother as a suspect but they will not say whether or not they have ruled out the father.
The Klaas Kids Foundation has set up a telephone hotline at (510) 500-5241 for the public to get updates on the family's efforts and activities.
People who have tips about Daphne's disappearance should call Oakland police at (510) 238-3641.