The senior Schooling, a retired businessman, had been undergoing treatment for liver cancer.
He had made public his diagnosis and has documented his treatment on Instagram via the family's joint account @cmjschooling.
Followers of the Schoolings were informed via social media what was happening as early as mid-June 2021.
In the latest update on Nov. 17, Schooling was in a high dependency ward due to "a (mutant) bug in his lungs".
His family had hoped that Colin would recover well enough to be able to enjoy his favourite food.
Colin was educated at Raffles Institution.
He did hurdling and played water polo and became a national softball player.
In 1983, he married May Yim.
The couple met at a Pesta Sukan softball tournament in Penang in the 1960s when she was part of the Perak team and he was representing the Republic in the Pirates team.
After three miscarriages, Joseph was born in 1995.
Colin and May spent more than S$1 million to help develop their son Joseph into a gold medal-winning Olympic champion in 2016.
They sold a house in Perth and cashed out on an endowment plan to pay for his training.
Top photo via Joseph Schooling/IG