It is a yearly affair for the Ong siblings to visit Bangkok and offer their prayers at the downtown Erawan shrine.
Ms Betty Ong, 69, a semi-retired administrative executive, was there with her sister Jane, 59, brother Wesley, 53, and his wife Jennifer, 41, on Monday when the worst bomb attack on Thai soil took place.
Ms Ong said there were two blasts, the second being very loud. All four suffered partial hearing loss.
"I thought it was some gas explosion. People were screaming and running away," she told The Straits Times on Wednesday.
"We are very lucky to be alive," said Ms Ong, who needed six stitches on her left thigh and has since been discharged.
Her siblings' injuries were more serious. Her sister Jane needed two operations, one to remove shrapnel in her leg and another on Wednesday night to remove the fragments in her left forehead.
Speaking to The Straits Times at a private ward in Hua Chiew General Hospital, the younger Ms Ong became emotional when she recalled the traumatic event.
"There was this blinding light and the next moment when I opened my eyes, my spectacles had been blown off by the impact. I felt as if my skin was burning off. I did think it was a bomb but I did not register the pain until I felt blood coming down my face," she said.
"I try to be positive but the images keep coming back to me. There were so many dead bodies. It's a very cruel thing. Very inhuman thing to do. These people owe the world an explanation. They cannot do this to innocent people," she cried. A psychiatrist is helping her cope with the post-trauma effects.
The Singapore embassy has engaged an interpreter to assist the Ongs at the hospital.
Mr Ong, an engineer, underwent a high-risk operation on Wednesday to remove a 5mm bullet pellet that had pierced and torn his colon and to mend the tear.
The impact of the blast also broke his right shin and he had a first operation for screws to be inserted to join the bone. A bullet pellet lodged in the muscles of his left thigh will not be removed because it is lodged near a tendon and nerves so there are possible side-effects.
The Ongs have no immediate plans to return to Singapore because their priority was to get complete treatment and to recover until they are fit to travel.
Mr Ng Su Teck, whose wife Melisa Liu Rui Chun was killed in the blast, said earlier on Wednesday that he hoped to return to Singapore with her body.
"If that is not possible, then perhaps a few days in between," Mr Ng, 35, told The Straits Times, referring to the time between his return to Singapore and his wife's body being flown back to Singapore.
He said he was waiting for Singapore's Ministry of Foreign Affairs to arrange for evacuation from the Thai capital.
The Straits Times understands he was discharged and due to return to Singapore on Wednesday night.
Speaking earlier at Ramathibodi Hospital, Mr Ng said he would speak to the media when he is back in Singapore and feeling better.
"Just let me rest and I do not want to talk about what happened," he said. "I don't want to make it a big thing."
Mr Ng sustained burns and his right leg was cut by glass shrapnel. His hearing was also affected.
Ms Liu, 34, died on the spot when the bomb blast ripped through the evening crowd at the Ratchaprasong intersection in Bangkok on Monday. The area is where the popular Erawan Shrine is located.
Mr Ng, who works in sales, and Ms Liu, an employee at AXA Singapore, had travelled to Bangkok with some companions for a holiday. Her brother was among the seven Singaporeans injured.
Ms Liu joined AXA Assistance in November 2013 and her colleagues remember her as someone with a spontaneous personality and hearty laugh. She was a loyal friend to her peers and well respected by all.
"She was a valuable member of Claims team liaising with the AXA Assistance network and partners across Asia," said Mr Philippe Demangeat, CEO of AXA Assistance Singapore. "Melisa... helped to organise several employee engagement and corporate responsibility events that contributed significantly to the culture of our company," said Mr Philippe Demangeat, CEO of AXA Assistance Singapore.
Monday's blast killed 20 people, many of them foreigners, and left more than 120 others injured.
The Erawan shrine reopened yesterday, with Thai monks leading prayers and devotees, including tourists, turning up at the site.