Positive identification of Azriel was based on clothing, the boy's mohawk haircut and "looking at pictures of him," Pierce County sheriff's spokesman Ed Troyer said. The body was found Thursday on Fox Island, southwest of Tacoma.
A ground search along the beach turned up no sign of the boy's 29-year-old mother who disappeared with him on Saturday night. She is still missing.
Divers on a boat searched as well and a Coast Guard helicopter and sheriff's office plane flew overhead. That search may resume Friday, depending on weather, Troyer said.
Smiley's abandoned minivan, partially submerged with its doors open, was found Sunday on a remote Olympia-area beach about 12 miles south of Fox Island. A wallet containing Smiley's driver's license, and some cash and credit cards, were found in the van.
Thurston County police had been leading the search for the pair since the van was found in their jurisdiction.
Jay Carver, Azriel's father who flew here from Buffalo, N.Y., this week, went to the beach where the boy was found. Troyer said the father was not involved in identifying the body.
"You really don't know what you have in your life until they're gone," Carver told KING-TV. "It's a sad turn of events."
Two mismatched shoes, a partially full and corked wine bottle, an inhaler and an orange ball have washed ashore since the van was found. Mealy said the items apparently belonged to the boy or his mother.
Smiley was heading from her home in Silverdale to her stepfather's house in southwest Washington when she and her son vanished Saturday night. Silverdale is about 16 miles west of Seattle, across Puget Sound.
Her fiance, Robb Simmons, told authorities she was a recovering alcoholic who had relapsed last week.
"We are grieving the loss of Azriel, and praying for Shantina. We are all severely hurting. We are getting the family together so we can grieve together, and so we can have some sort of peace right now," Simmons told the television station late Thursday.
Mealy said there was no indication that a crime took place inside Smiley's 2005 Dodge Caravan.
The Pierce County medical examiner's office planned an autopsy Friday to determine the cause of death.
Anyone with information on Smiley's whereabouts should call Thurston County Crime Stoppers at 360-493-2222 or the Thurston County Sheriff's Office at 360-786-5500.
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