KUALA LUMPUR, April 22 -- Puan Noor Aishah, Singapore's former first lady and widow of the country's first president Yusof Ishak, passed away peacefully at the Singapore General Hospital early this morning. She was 91.

Her death was announced by Singapore Prime Minister Lawrence Wong in a Facebook post today. Wong said he was deeply saddened by her passing, describing her as a "steadfast pillar of support" during Singapore's early years of nation building.

"With grace and quiet strength, she stood by Encik Yusof Ishak and steadfastly supported him throughout our tumultuous years of nation building," Wong wrote.

He also highlighted her charitable contributions through organisations such as the Singapore Red Cross and the Singapore Musli...