Fellow climbers were surprised to see Singaporean Minnal K. Dhayalan reach the 5,364m-high Everest base camp three years ago - at the age of just nine.
"I had the fitness, so age wasn't a barrier at all," said Minnal, now 12.
But had she wanted to go from base camp to Everest's summit, she would have had to wait until she was 16 - the minimum age for someone wanting to attempt the climb.
On Tuesday, Malaysia said it will review safety protocols for climbers following last Friday's Mount Kinabalu tragedy, possibly raising the minimum age to 15.
The official Mount Kinabalu website states that climbers should be at least 10 years old.
Experienced mountaineers welcomed the proposal, saying that older children tend to have the emotional resources to deal with emergencies better.
However, they added that the age bar should be used as a guideline to warn parents and schools of the level of risks involved instead of being a rule that is strictly enforced, as a person's age may not be an accurate reflection of his fitness.
According to the Malaysian media, Sabah is considering the possibility of allowing only those aged 15 and above to climb the mountain.
However, the Sabah tourism office told The Straits Times that its age advisory of at least 10 years old for children is a "suggestion".
Rasip Isnin, secretary of the Singapore Mountaineering Federation (SMF), said such limits can be subjective and arbitrary.
"A young child may be better trained or have greater fitness than an older teenager or adult," he said.
Currently, anyone wanting to be accredited by the Singapore National Climbing Standards has to be at least 13 years old.
Mr Rasip said SMF may follow Malaysia's proposal and tweak this age limit, depending on the outcome of investigations into the tragedy.
"Most places don't have an age limit, but some established agencies and guides require you to show them that you have climbing experience," said mountaineer Kumaran Rasappan, a 31-year-old doctor who has climbed more than 10 mountains, including Everest.
He added: "On mountains, people do get injured on a regular basis and people do die. A young person might not be emotionally ready to deal with this."
Several fatal accidents have occurred on the slopes of Mount Kinabalu. Last year, a 22-year-old German tourist died from a fall after she climbed over a safety rail on a summit.
Sabah education director Jame Alip found the slopes of Mount Kinabalu steep and dangerous when he did the trek at age 20. "I cannot imagine how it would be like for young students," he said.
Though Tanjong Katong Primary School has been using the Mount Kinabalu route for seven years, Mr Rasip said the bulk of students who head there every year are at least of secondary-school age or older.
Raj Kumar - director of IPC Tours, which organises about 500 overseas school trips a year - believes it is a good idea to tighten the age guideline for the mountain.
"A five-year gap plays a big difference in the emotional maturity of children," he said.
"When emergencies happen, older children may be more confident in making better judgments and reacting faster."
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