The U.S. Coast Guard says one of two boaters missing for a week has been found alive, drifting on an inflatable life raft off the coast of Massachusetts.

The Coast Guard on Friday suspended its search for 54-year-old Linda Carman and her 22-year-old son, Nathan, of Middletown.

The mother and son disappeared Sept. 18 after leaving a Rhode Island marina to go on a fishing trip in a 31-foot aluminum fishing boat named the Chicken Pox.

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The Coast Guard in Boston says Nathan Carman was found Sunday by a freighter, the Orient Lucky, about 100 nautical miles south of Martha's Vineyard.

He was listed in good condition and reportedly told the Coast Guard by phone he had food and water in his life raft.

Linda Carman's whereabouts remain unknown. The Coast Guard said Monday they do not plan to reopen the search for Linda and that it's now "beyond the survivability window."

Nathan Carman told the Coast Guard the boat they were on started taking on water and when he got in a life raft he couldn't find his mother, according to a Coast Guard spokesperson.

Nathan Carman, who has Asperger's syndrome, a form of autism, disappeared in 2011 after he became distraught over the death of his horse, his parents said at the time. After a widespread search, the then-17-year-old Carman was found in Sussex County, Virginia. Police said he had taken a bus to Virginia and bought a scooter that he had planned to ride to Florida.

A friend of Linda Carman said she was ecstatic when she learned the boater's son was found alive. But Sharon Hartstein's feelings quickly turned to terror when she learned her friend was still missing.

The Hartford Courant reports that the Carman family was also struck by tragedy in 2013 when Linda Carman's father -- John Chakalos of Windsor, Connecticut -- was found dead in his home of a gunshot wound to the head. No arrest has been made in that case.

Nathan Carman grew up in Connecticut, but has lived in Vernon, Vermont, in recent years.