The call that they had been praying for finally came on Friday.
Their son, Mr Mohamed Faizal Abdul Salam, assured them that he was fine.
But the 28-year-old had suffered head injuries and needed an operation in a hospital in Sabah, Malaysia, said Mr Abdul Salam Abu Bakar, 73.
Mr Faizal was among the eight teachers and 29 pupils from Tanjong Katong Primary School, who were at Mount Kinabalu when a 6.0-magnitude quake struck on Friday.
A relieved but still worried Mr Salam said it was a short 10-minute conversation with his son before the line was cut off.
Mr Faizal had called from a different number as his mobile phone's battery was flat, said his mother.
Mr Salam told The New Paper on Sunday: "He called back and told us not to worry.
"Before this, we couldn't reach him. We were very worried, we cried and cried."
Mr Salam and his wife, who declined to be identified, were seen at the school yesterday morning.
He said: "We came because many parents come here to get updates."
He added that his son, an only child, has been teaching at the school for three years and is a Primary 6 teacher.
Mr Faizal is expected to return to Singapore today.
This article was first published on June 08, 2015.
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