They departed Ram’s Point Marina in Point Judith, Rhode Island Saturday evening in the Chicken Pox, a 31-foot center console boat. Carman told the Coast Guard the boat sank at Block Canyon.Linda Carman’s son, Nathan Carman, was rescued from a life raft by a passing freighter Sunday after seven days on the Atlantic. “Clearly something happened, but I don’t know what, and I don’t know how it could have been prevented”.A second person at the marina told police that Carman told him he had removed the “trim tabs” from his boat because he believed they “were not doing the boat any good”.Since Nathan Carman has been questioned about his ill-fated fishing trip, it’s been revealed he was considered a suspect in the 2013 murder of his grandfather, John Chakalos, of Windsor.Carman returned home on Tuesday and has not been charged with a crime, authorities said.Carman’s attorney Hubert Santos said his client “fully cooperated” with the Coast Guard after he was taken to Boston on Tuesday by the freighter that rescued him.The Courant reported that Windsor police submitted a murder arrest warrant for Carman to a prosecutor in July 2014, but the warrant was returned unsigned.”I know I wasn’t responsible for the boat sinking”, he told ABC.The chief of the police department in South Kingstown, Rhode Island, said Thursday it is investigating “the facts and circumstances” surrounding Linda Carman’s disappearance along with state and federal authorities in Vermont, Connecticut and MA.A search warrant said that Carman was the last person known to have seen Chakalos alive, that Carman had bought a rifle consistent with the one used in the crime and that he discarded his computer hard drive and Global Positioning System unit used around the time of the shooting.Chakalos left more than $42 million to his four adult daughters, including Carman’s mother. He said police interviewed Chakalos’ relatives, including Nathan and Linda Carman, as part of their investigation.Meanwhile, police in South Kingstown, Rhode Island – from whence mother and son set off on September 17 – reported in an affidavit obtained by NBC News that Carman’s boat “was in need of mechanical repair” and that he “intended to go fishing farther off-shore in a different location than what were his mother’s intentions and understanding”. “If I hadn’t asked my mum to go fishing with me that weekend, she would still be alive with me today”.”I’m lucky to be alive, I lost my mother and very, very hard people, especially The Hartford Courant are trying or, raking up the time when I lost my grandfather”.Police began eyeing Carman, then 20, in his grandfather’s slaying after his mother, Linda Carman, told them her son failed to meet her in Glastonbury at 3 a.m. that morning to drive to Rhode Island as discussed, the paper wrote.”She was convinced he had nothing to do with it”, Klein said.Images shared by a family friend show Nathan and Linda in separate images holding fish on a boat.Clark Carman, Nathan’s father, who lives in California, was in Middletown on Wednesday. The documents also said Carman had several alarming episodes while he was a high school student, although no details of those incidents were given. He said he grabbed survival gear, then looked back and she was gone. Authorities said her son ventured about 80 miles further out than she had anticipated and are looking into what mechanical repairs Nathan Carman made “upon his own volition which could have potentially rendered the boat unsafe for operation”, according to an affidavit. Their search warrant indicates authorities think Carman was handling boat motor repairs himself and the vessel might not have been seaworthy. They partnered with Vermont authorities to search Nathan Carman’s home in Vernon for evidence of reckless endangerment.Family members also told NECN that Carman suffers from Asperger’s syndrome, which is a form of autism.