Iona Costello , 51 , and her daughter Emily , 14 , missing since late March . Pair from posh suburb of Greenport , Long Island , often went to shows . Video shows them with suitcases , but relatives began to worry after daughter began missing school . Mother told workers at her horse farm that she 'd be 'back on Tuesday ' Relative said that Costello had been 'under a lot of stress ' during the legal battle over her husband 's estate .
Iona Costello , 51 , and her daughter Emily , 14 , missing since late March . Pair from posh suburb of Greenport , Long Island , often went to shows . Video shows them with suitcases , but relatives began to worry after daughter began missing school . Mother told workers at her horse farm that she 'd be 'back on Tuesday ' Relative said that Mrs Costello had been 'under a lot of stress ' during the legal battle over her husband 's estate .