When Emeritus Senior Minister Goh Chok Tong heard that Mr Lee Kuan Yew, 91, had died yesterday, tears welled up in his eyes.
Less than two hours later, he paid tribute to the man whom he described on his Facebook page as his "leader, mentor, inspiration, the man I looked up to most".
Later, in a letter to Prime Minister Lee Hsien Loong, the late Mr Lee's son, Mr Goh said that he and his wife were "deeply distressed" by the news:
"Your family has lost its patriarch, and Singapore its key founding father. We share your grief, and can only offer you and your family our profound condolences.
"Mr Lee Kuan Yew dedicated his life to Singapore. He lived and worked to build a nation and to advance the well-being of Singaporeans. For many Singaporeans - members of the pioneer generation in particular - he will forever be in our grateful hearts. He gave us a country we can be proud of, a home to bring up our family and a better life we can aspire to."
Mr Goh, 74, who took over the reins as Prime Minister from Mr Lee in 1990, said Mr Lee helped him succeed in the role: "Outside your family, I probably have benefited more than anyone from his guidance and advice."
They "enjoyed a warm relationship" and had lunch fortnightly until Mr Lee grew unwell, he said.
Mr Goh last saw Mr Lee on Feb 5, when he was admitted to Singapore General Hospital with severe pneumonia. "It pained me to see him sedated and unaware of his surroundings," Mr Goh wrote.
He recalled that Mr Lee had been devastated in 1992 to learn that PM Lee - then 41 and Deputy Prime Minister - had been diagnosed with lymphoma.
"Outwardly, however, Mr Lee braved on with little hint of his personal emotions to his hosts. His stoicism and message were clear - we must not be deterred, however daunting life's interventions," Mr Goh wrote.
"Your father's virtues, morals and habits - integrity, resilience, hard work, discipline, frugality, daily exercise, to name a few - are legendary, as are his demands of high standards of performance. Much of today's 'Singapore DNA' can be traced to his character, philosophy and values."
Mr Goh encouraged PM Lee to take heart from his countrymen's respect for and gratitude to Mr Lee, to carry on with his father's work.
"As Prime Minister, you lead a nation in mourning the demise of its greatest son, even as you grieve the passing of your father. Condolences cannot erase the pain of your bereavement. May Singaporeans' deep respect for your father and their gratitude for his lifelong service to our nation give you the strength to continue his life's work of making Singapore strong, secure and prosperous," he wrote.