Naya Rivera's four-year-old son told police he watched her disappear beneath the water, an officer has said.A search and recovery operation is still under way after the actress went missing on Wednesday while on a rented boat with her four-year-old son at Lake Piru in California.Police told the PA news agency that Josey Hollis, who is safe and well, observed his mother disappear under the waves during their boating trip on Wednesday.Josey was found asleep and alone on the boat while wearing a