Kaia Fina of San Clemente was last seen Thursday night; she was reported missing Friday.
Orange County Sheriff's deputies say she may be with her biological mother, Sera Fina, who does not have legal custody of her daughter.
The child may be in her vehicle, a 2007 black BMW X3, with a California license plate of 7RRY771.
If you have information regarding the incident, you can call 714-647-7055 or contact the Orange County Sheriff's Department Commander at 949-770-6011.