Mrs Lena Moi died on Thursday evening, a few hours after meeting her husband and two of their daughters at the family's Kabimoi home in Koibatek District.
Mrs Moi, who was about 75, died at 8pm as her driver, Mr Solomon Komen was taking her to the Mercy Mission Hospital at Eldama-Ravine Town, some 10 kilometres from her 180-acre Kabimoi farm. Eldama Ravine is about 60 kilometres from Nakuru.
According to relatives, she had been suffering from high blood pressure for a long time. The former President and daughters Doris and Jennifer visited her on Thursday afternoon, after they received information about her failing health.
She prayed with them and was jovial throughout their stay. They are said to have stayed with her from 5 pm to 6.30pm.
Mr Moi was informed of her death later in the evening.
Relatives told the Nation at the home that her condition worsened soon after her husband and daughters left.
The body was transferred to Nairobi on Thursday night.
Her eldest son, Mr Jonathan Torotich, and his wife were among the first to arrive at the home yesterday's morning. Mr Toroitich lives a few kilometres away.
He had just left the mother's home when the Nation team got there.
District Commissioner Christopher Musumbu led the Koibatek security committee in signing the condolence book at the home.
A neighbour, Mr Joshua Kitton, said Mrs Moi had two years ago been taken to the Nairobi hospital for treatment.
Last week, when Mr Kitton visited her, she complained of chest pains but was cheerful.
"Any time visitors came to see her, she would welcome them and at the end of the visit, say a word of prayer," Mr Kitton said.
Mr Kitton said the late Lena and the former President moved to the farm in 1969.
"Since that time, we have been close neighbours and we go to AIC (African Inland Church) Ngorobich," He said.
She was the second born in a family of four. One of her brothers, Mr Eric Bomett, is a former assistant minister. Another, Mr Harun Bomett, is a retired principal principal magistrate and a vice-chairman of the Kenya Football Federation (KFF).
According to the driver, Mrs Moi was cheerful to her last hours and no one would have suspected that she would succumb to hypertension. He said he used to drive her mostly to church or shopping.
"We used to go together to visit some of her children and friends in the neighbourhood," said Mr Komen.
The chairman of the Kenya National Federation of Agricultural Producers (dairy division), Mr Joseph Ng'era, described the Mrs Moi as a generous, humble and self-effacing personality.