Clearlake Police Chief Craig Clausen said it appeared Mikaela Lynch of San Francisco had wandered away from home Sunday afternoon on her own and wound up in Cache Creek. No foul play was suspected, the San Francisco Chronicle reported.
The girl, who had the mental capacity of a 1-year-old, had been playing on a trampoline with her younger brother and was left alone briefly when he ran inside to avoid a bee, police said.
"It's really tragic," police Sgt. Nick Bennett said. "We had hopes it might turn out differently."