Iona Costello's stepson, George Costello Jr, 45, was staying nearby at the time. He also has a long history of drug arrests (mugshot from April) The stepson of a Long Island mother who went missing with her daughter last month has a long criminal record and was jailed again just days after she disappeared, a report suggests. George Costello Jr is currently in jail in Florida on apparently unrelated charges and has been described by relatives as a 'mixed-up' kid.' Iona Costello, 51, and daughter Emily were visiting Manhattan when they were last seen on March 30 near their home in the the wealthy seaside village of Greenport. Their car was found in a parking garage on 42nd street in Manhattan, but the pair, who often went into the city for theater and art museums, left no other trace of their whereabouts. Iona's husband died in 2012 from a heart attack, and she is believed to have been 'under a lot of stress' because of a legal battle with four of his five adult children from previous marriages. The New York Daily News have reported Iona's stepson Costello Jr, 45, was visiting Hamptons Bay, New York, at the time, and relatives said he has never got on with the family. He has a long history of drug arrests and is currently in Palm Beach Detention Center following an arrest for a 'domestic dispute' when he returned to Florida. His fiance, who wanted to remain anonymous, told the Daily News  it was a 'weird coincidence', but insists she was with him the whole time. Speaking from the prison, he told the newspaper he was visiting his Hampton Bay home at the time and flew home on April 1, two days after the pair went missing. George Jr, who has at least 10 arrests to his name, according to court records, says he didn't have a close relationship with Iona. He said the last time the pair spoke was at his father and her husband's funeral. 'She's a hardworking lady who loves her horses and takes care of them really well. She's a good mother,' he told the Daily News. Scroll down for video . Iona Costello, 51, and daughter Emily were visiting Manhattan when they were last seen on March 30 near their home in the the wealthy Long Island village of Greenport . Iona's mother, Diana Malcomson, also insisted George Jr wouldn't want to harm the pair, but said he was a 'mixed-up kid'. Her brother-in-law is also facing a criminal case. John Costello, is  facing vehicular manslaughter charges after he allegedly drove his pickup truck into oncoming traffic last December in Greenport, New York. Iona's brother-in-law John Costello, is facing vehicular manslaughter charges after he allegedly drove his pickup truck into oncoming traffic last December in Greenport, New York . Relatives of the 'quiet Irish family', who own a horse farm on Long Island's North Fork, reported them missing on Tuesday. Iona, who was her late husband George's third wife and inherited his entire estate along with her daughter, had been 'under a lot of stress' because of a legal battle with four of his five adult children from previous marriages. 'She can't sell anything. She can't do anything because everything is in court,' an unidentified relative told the New York Daily News. 'I don't know if she's having a nervous breakdown. I don't know if somebody has kidnapped them,' the unidentified family member said of the Costellos' long absence from their home and farm. Costello's adult children have argued that the will granting the estate to Iona was improperly executed, according to Novick Law Group. A Long Island court sided with the adult children last year, and Iona Costello is appealing. Amanda Hurwitz, one of George's daughters who now lives in Connecticut, refused to comment to Daily Mail Online on the report or her stepmother's disappearance. The widow's trip into New York was originally only supposed to last for several days. 'She said she was going to Manhattan for Easter,' Iona's mother Diana Malcolmson, 80, told Daily Mail Online. Iona Costello's husband George, the co-owner of Costello Marine in Greenport, died from a heart attack in 2012 . The grandmother, who lives in nearby Shelter Island, New York, said police told her that surveillance footage from the parking garage showed Mrs Costello and Emily walking away from their car on March 30, holding suitcases and laughing. She said that she spoke regularly with her daughter, but had not heard about any plans for extended vacations. While trips into New York were fairly normal, Emily being out of school is not. The ninth grader had been scheduled to return to Ross School in East Hampton from her Spring Break this past Tuesday. Police have reportedly told Iona's mother there is surveillance video of them leaving a parking garage laughing . The mother had told workers at her farm that she would be 'back on Tuesday' but did not return on March 31st, April 7th or April 14th. Workers at the horse farm say it is strange for Mrs Costello not to be in contact with them about raising the animals. Southold police Chief of Police Martin Flatley told Daily Mail Online that his force does not expect any foul play. He said that he does not currently have any hard evidence to point to the mother and daughter being in danger. Relative Jane Costello said that calls to both Iona's and Emily's phones go straight to voicemail.
Iona Costello, 51, and daughter Emily were last seen on March 30. Were heading into Manhattan to visit the theater when they disappeared. Mom's stepson, George Costello Jr, was visiting the Hamptons at the time. Has a long criminal record and has a tense relationship with the family. He returned to Florida two days after they went missing and was jailed. Police have so far said they do not suspect foul play is involved.