Two months later, on a chilly morning in early 2006, Lisa and Hannah sit on the sofa in the front room, looking out the window, past the snow in the front yard toward a vista of houses and lake and gray sky. It's a nice day to be inside, if you're someone who likes that sort of thing. Lisa shifts her torso on the sofa, hugging the arm of her sweatshirt, trying to find a comfortable position.

After Hannah leaves the room, Lisa slides further into the cushions to talk about her life. She and Steve had had a perfect life: good jobs, frequent trips to the backcountry and far-off places. They had been so committed to the idea of the open road that they had embedded it in their daughters' names: Lillian Marrakesh, after the Moroccan city they loved, and Hannah Moorea, for an island in Tahiti. Now she will be what she calls a "soft mom," reading books to the girls, helping them with homework, giving lots of hugs and cuddles. That's a good mom role, she says, but she had wanted to show them how to be rugged in the world.

She worries that she will burden Hannah with constant requests to "open this" and "pick up that." With Lily, Lisa needs what she wryly calls "adult supervision," because in an emergency she won't be able to rescue the baby, unthinkable to an emergency room nurse. A nanny, 21-year-old Sammie Bickmore, has helped care for the baby since Lisa was in the hospital, and even now, when Steve or Sammie leaves the room and only Lisa is left, Lily cries.

"I didn't wait this long to have children to have someone else get up with my kid in the middle of the night or someone else watch my kids five days a week because I don't have the stamina," Lisa says.

But little by little there is a new normal. Lily likes to snuggle with Lisa now. Hannah likes to lie next to what she calls Lisa's "baby arm" and uses Lisa's hook hand — the one Lisa has named "Alfred" — as a carry-all for gum wrappers and hairbands. Not long ago, when the children in Hannah's preschool class were asked what makes them happy, Hannah's response, later tacked to the classroom door, was "I'm happy because my mom gives me hugs and kisses."

· · · · ·

Lisa and Lily are learning to walk at the same time, Lily at home on pudgy baby legs, propelled by instinct, Lisa in the rehab room at University Hospital, on legs made of titanium and acrylic.

Learning to walk on artificial legs, at 44, means building up the glutes so they're strong enough to launch the legs forward, and training the brain to think about the relationship between knee, heel and toe. Today Lisa is dangling, attached to an elaborate harness that looks like an amusement park ride. Strength comes through exercise but also from the sheer effort of hanging from the harness, trying to move legs that aren't her own. They hang, like marionette legs, from the sockets that fit over her stumps. At the bottom are two running shoes.