Last interview with world's oldest mum

At best, Christian and Pau Bousada, the Spanish toddlers who were orphaned eight days ago when their 69-year-old mother died of cancer, had spent barely two years of their short lives with their world-famous parent.

But a documentary to be broadcast this week will suggest they spent even less time with Maria Carmen del Bousada de Lara, a pensioner who became the world's oldest mother at 66 through anonymous sperm and egg donations, heaping further controversy over decisions to allow women long past the menopause to receive fertility treatment.

Ms Bousada's poignant interview from beyond the grave, which was recorded only months before she died, revealed a mother barely capable of looking after her twin boys, who have been orphaned at the age of two. "I think I'm putting this on the wrong way," she says, while changing one of their nappies.

The interview, the first and last time she spoke publicly about what it was like to be the world's oldest mother, depicts a fraught, frail-looking woman who could barely muster the energy to take the boys out for a short walk.

Ms Bousada, who lied about her age to American fertility doctors to get round age limits, only to develop ovarian cancer six months after giving birth, said: "I don't know how much time I have left with the boys. I don't have much hope for Barcelona. We'll have to see if they will treat me. If they don't, I'll be with the boys for as long as God lets me. I have a tumour. A bad tumour. Cancer, cancer is what I've got. They've told me they don't know how long I will last. And to enjoy myself as much as I can."

Her illness meant she was incapable of looking after her sons at night, the film revealed. The pair, who will have to rely on others to tell them about their mother, spent their nights with their cousin, Ms Bousada's 35-year-old nephew, and his wife. He was also their godfather and will bring up the boys following their mother's death.

Ms Bousada, who had said she thought she would live to 101, like her mother, said she never told Christian and Pau she was likely to die. "They're still babies, so I haven't told them. They're too young for these things."

The film also features her brother, Ricardo, who criticised her for getting pregnant. "We all adore the children, but from outside and of course inside the family there are those who say she should not have done this. I think she has done this too late in life. It was madness, but now they are here we love these beautiful boys," he said.

Her interview will be broadcast on Thursday in a Channel 4 documentary about the world's oldest mothers.