KUALA LUMPUR - One Indonesian family cancelled a planned trip to Singapore because the family patriarch had fallen ill. The decision in turn saved their lives.

Christopher Incha Prasetya, 10, cried when his parents cancelled the four-day visit to Singapore because of his grandfather's illness.

Christopher, his parents and two siblings were among those who didn't show up after buying tickets for Sunday's morning's flight.

"The kids were still on holidays and Christopher was very upset when we said that we couldn't go after all," his mother, Inge Goreti Ferdiningsih, 37, said by phone from Surabaya, Bloomberg reported.

"When we told him the plane was missing, he didn't believe us until we showed him the tickets."

Ms Ferdiningsih, an accountant, said she and her businessman husband, Chandra Susanto, paid more than 8 million rupiah (S$853) for return flights on the low-cost carrier for their family, which also includes seven-year-old daughter Nadine and son Felix, five.

They booked the trip in June and had planned to spend three nights on Sentosa, with the children eager to visit a water theme park. With her father ill, Ms Ferdiningsih said they decided to call off the vacation the day before the flight.