"You can't say enough," Brent King said. "It is so heartwarming to see the effort that's been being given. It's what sustains me every single moment. It's a testament to who my daughter is."
Gardner, of Lake Elsinore, was arrested outside a restaurant in Escondido. He was convicted of lewd or lascivious acts with a child under 14 years, according to the California sex offenders registry Web site.
Chelsea is 5-feet-5 inches tall and 115 pounds, with strawberry blond hair and blue eyes.
She is a member of the San Diego Youth Symphony and a straight-A student at Poway High School, where she is due to graduate this spring.
The sheriff's department asked that anyone with information about King's whereabouts call 858-565-5200.