Rausings had been due to enter drug clinic She was there and she didn't hear from him. She got worried so she came back home to get him to go back with her. She said that her daughter had celebrated last Christmas with the family in Barbados but Mr Rausing was not there. "She didn't stay very long and went back," she said. The family last heard from Mrs Rausing on May 3 when she sent a text to her father. Her mother said: "They were getting ready to go. Her husband had his passport and they were getting ready to go back to California. We had high hopes. Police found the body of Mrs Rausing at the couple's home in Chelsea earlier this week, several hours after they had stopped her husband for driving "erratically." He was later arrested in connection with his wife's death but questioning was halted on Tuesday when he had to be taken to hospital. Detectives suspect that Mr Rausing, an heir to the Tetra Pak fortune, had lived with his wife's body for up to a week while he went on a drugs binge. She appeared to have suffered an overdose but pathologists have been unable to find an immediate cause of death due to the condition of her body and have ordered further tests. Mrs Kemeny believes her daughter died because she had a heart condition which was exacerbated by long-haul flying. My son-in-law has been cleared. It was extremely distressing, but we found out from the coroner that they didn't find anything wrong. She had a heart condition and they found her pacemaker. They were going to use that to identify her but that wasn't necessary. Unfortunately, I think the plane did something with her heart. She had never gone back to the doctor after the valve had been replaced. I think it was this flying back and forth from California to London. Mrs Kemeny and her husband Tom, 71, a former Pepsi Cola executive, live in a house overlooking a golf course on an island off South Carolina. They were in England when Mrs Rausing's death was announced, and Mrs Kemeny returned home on Wednesday. She has been unable to speak to Mr Rausing since his arrest. She said her daughter would probably be buried in the United States, and that there could also be a memorial service. "We're going to have to speak to her husband and he is in hospital," she said.