Mrs Ladeji died on Monday after a brief illness.
The development was announced by Fayose on his Twitter page
He wrote, "On behalf of my family, I announce the death of my immediate elder sister, Mrs Moji Ladeji. She died today, after a brief illness."
"We are pained by your departure, but consoled by the God-fearing and exemplary life that you lived. May the soul of Sister Moji Rest In Peace."
