Nanny on doomed Learjet made haunting final video call to sister before plane crashed as 911 calls from witnesses reveal utter panic

The nanny traveling on the doomed Learjet plane that plummeted into the ground made a final video call to her sister before her death, her family has revealed. Anita Maria Cetina, 24, the nanny with the Robinson family who chartered the jet, died on board the horrific crash last Sunday, which occurred near West Palm Beach, Florida. She was just weeks away from celebrating her 25th birthday, and called her sister Angie Ramirez Cetina moments before the group took off in the doomed plane. Speaking to The US Sun, the devastated sister said: 'We did a video call, she showed me the children, she showed me the plane. She was very happy. 'She was truly happy because she had never been to the Bahamas, and even though she was working, she didn’t see it as work. She enjoyed it. She loved the job she had. She loved the children very much. She loved the Robinson family dearly.' Investigators are working to determine what caused the business jet to crash on the voyage from Austin, Texas, to the Bahamas, killing pilot Jeffrey Gregory, 55, and 20-year-old co-pilot Nathalia Gadelha Filgueiras.Adam Robinson, his wife, Helen Sharp, and their children, Emma, four and Charlie, two, and Robinson's friends Rachael Reed and Charmi Fehr were also on the flight. All nine souls died. Cetina's sister has seen the video of the plane exploding with her sister on it and said she 'didn't want to accept that it might be my sister on the plane,' she told The US Sun. Her mother later confirmed it was the flight carrying her sister. The children's nanny, Anita Maria Cetina, died on the doomed flight last Sunday She was just weeks away from celebrating her 25th birthday, and called her sister Angie Ramirez Cetina moments before the group took off in the doomed plane The plane nosedived into the ground in Florida, exploding into a fireball 'My sister and I shared so many things together. We have so many memories,' Angie said. 'She and I were inseparable.' New 911 calls made by frantic Florida residents on the ground have also shed light on the traumatic event as it unfolded - with some telling police they thought the explosion was caused by a bomb. 'There was an explosion,' one woman told 911, according to NBC Miami. 'I think an airplane, a rocket, something fell from the sky.'We felt our house shake, and then we heard an explosion when we ran outside. We didn't see what the actual thing fall [sic], but sparks came out, and there was a bunch of smoke.'Another person told 911 they heard a 'really big explosion.' The country was also moved by the air traffic control audio of Filgueiras, as she relayed information to the controller as the flight nosedived. She is heard saying: 'Seven two two bravo delta, we're descending 8,000... mayday mayday... we're descending 10,000ft per minute.'Seconds later, she screams: 'Declaring emergency, declaring emergency, we are in an overspeed condition,' before her voice breaks as she shrieks, 'descending 20,000ft per minute... we're going to crash into the ground.'Jeffrey Gregory, 55, and 20-year-old co-pilot Nathalia Gadelha Filgueiras were operating the plane Adam Robinson, his wife, Helen Sharp, and their children, Emma, four and Charlie, two, chartered the plane Robinson's friends Rachael Reed and Charmi Fehr were also on the flight. All nine souls died'I'm here with you, talk to me,' the air traffic controller says in an attempt to calm the situation.The pilot says: 'We are descending 22,000ft, and we are banking 60 degrees.' This means the wings were tilted at a 60-degree angle, meaning the jet was nearly completely sideways.'We're out of time,' she screams.The Daily Mail has chosen not to publish the final seconds of audio, which are extremely distressing.A massive crater marked the impact site, ringed by a wide field of scattered wreckage.