Felicia Boots (above) has admitted killing her two babies who were found dead at the family's upmarket home.
She pleaded guilty to the manslaughter of 10-week-old Mason and his 14-month-old sister Lily in May.
Boots wept at the Old Bailey as she admitted the killings. She pleaded guilty to manslaughter on the grounds of diminished responsibility.
She was ordered to be detained at a psychiatric unit and the court was told she would be given full support and care if she became pregnant again.
Boots, who wore a black suit and white blouse, sent a note to the court which was read by her counsel Kate Bex.
It said: "May 9, 2012, is a day I will be eternally sorry for. It should never have happened.
"It troubles me more than anyone will ever know. Part of me will always be missing. I am a good person. I am a good mum and I never meant any of this to happen. I am truly sorry."