Francesca Segal gave birth to twin girls ten weeks too early. This is the affecting story of what followed - how she learned to bond with her fragile new daughters and how, under the most challenging of circumstances, she came to understand what it really means to be a mother. It is also a celebration of women's friendship and the vital and sustaining bonds between women in extremis, a sisterhood formed in the 'mother ship' of the intensive care unit.These two on the left, side by side in two incubators, these two says the doctor, they are my daughters. Baby A is doll-sized; B is smaller still. Their skin is too fragile for clothes. They are both wearing white cloth hats, white Velcro sunglasses, and their noses and mouths are obscured by a mask delivering Continuous Positive Airway Pressure, CPAP, to force their stiff, unready lungs to breathe. A feeding tube disappears between their lips, and down their throats. Their faces remain a secret known only to each other. I press my face to the glass. They are farthest from me, and the farthest from one another that they have ever been. I do not recognise them. They are otherworldly in their strangeness, and oceanic in their beauty. They are half-beings in the half-light and in an instant my heart shatters, and I become half a mother, twice. During this extraordinarily tense time, Francesca remains observant, capturing the situation with her first-class novelist's eye - wry and witty, eloquent and touching. This is a potentially devastating story rivetingly told, about fear and courage and hope. It will speak to all parents, on their journey to comprehend the demands and especially the joys of an extraordinary new relationship.