Evanescent: 1) Vanishing, fading away, fleeting. 2) tending to become imperceptible, barely perceptible.
In the morning, before she wakes, James watches the evanescent outline of Lily's burning hair against the sunrise. She sleeps on her front, though the doctor says it's bad for her breasts and she should stop soon. Lily says that soon she wouldn't be able to sleep on her front, and she'd rather make the most of it while she can.
James doesn't care, not about anything, as long as Lily is comfortable and rested. He still believes it was stress, last time, that caused the sudden twist of Lily's face and the smashed plate on the floor as she dropped it and sank into a crouch. He remembers the sharp smell of that day, mixing with the rhubarb crumble in the oven, and the limpness of Lily's hand in the too-bright lights of the Muggle hospital, and the way she never cried, just woke and asked for the baby, was it alright, was it alright.
This time is different. James feels it in the firm curving of Lily's belly, the strength of her conviction, the shine in her hair and eyes and laughter. He feels it in his gut, his manhood, his incipient fatherhood. He feels it in the floating strands of Lily's hair, glowing gold against the orange sky, and in his child, solid and real and happening inside Lily. Not about to fade away.