"When they encounter something they can't do," says their mom Darla Garrison, "they don’t dwell on it too long."
Indeed, Macey and Mackenzie – formerly conjoined twins who each have one leg – rely on prosthetics, but in every other way keep pace with their triplet sister Madeline.
Born attached at the pelvis with a shared third leg and entwined intestines, Macey and Mackenzie faced hurdles that would have challenged any family. Yet they carried an extra burden: Their birth parents, who had not seen a doctor during the pregnancy, had drug problems and were unable to care for them.
Happy HomeEnter Darla and Jeff Garrison. Over the years Darla, 42, a homemaker, and Jeff, 52, a construction worker, had welcomed several neglected or medically fragile foster children into their home, only to see each one move on. But they'd always wanted girls to expand their biological family of three healthy boys – Tyler, 20; Matt, 17; and Luke, 16.
Two years after doctors at Children's Hospital Los Angeles separated Macey and Mackenzie in 2003, the Garrisons adopted all three girls and moved from California to a farm in Indianola, Iowa. Their goal, as they told PEOPLE for a 2010 profile, was to create the kind of country childhood Darla and Jeff themselves had known and treasured.
Since then, Macey and Mackenzie have thrived, says Linda Kontis, cofounder of the foster-care agency that placed them.
"When you raise children who are handicapped in any way, when they're surrounded by people who treat them like regular kids, that becomes how they see themselves," Kontis says. "It wasn't just Darla and Jeff, they took in these girls as a family unit. And that's why they’re fabulous kids today."
A Bright FutureMacey and Mackenzie – who each weighed 2.2 pounds at birth – have overcome learning delays to be almost equal with their peers when they enter fifth grade in the fall.
"The girls have succeeded through hard work and the commitment by their family. Their progression is wonderful and inspiring," says Children's Hospital Los Angeles Pediatric Surgeon James Stein, who performed the multi-staged separation in 2003.
Courtesy Garrison family
And along with Madeline, all three girls have embraced household chores, including washing dishes, putting away laundry, feeding the cats and dogs to help out their mom, who was inspired by her experience with the girls to begin studying last year for a degree in physical therapy.
"I see them actually maturing," says Darla. "Now that I'm in school, I'm not as available, and they've really stepped up. They're pretty proud of that. They do a lot for 10-year-olds, really."
But 10-year-old girls they still are. "We used to have Bieber fever, but we've outgrown it," says their mom. "We're loving on Hunter Hayes these days. And also One Direction."
Macey and Mackenzie's rapid growth required them to swap out new prostheses three times this past school year.
"We're not to the point yet where they can just go out and about with their prosthetic legs," says Darla. "It's a balance issue. You have to train and train, and that's what we're doing with them at school."
Crutches are a constant, as are the ostomy bags that each of the girls must wear and change frequently – the primary excuse for their occasional down moments.
"Ostomies do upset your daily life," says Darla. "That's a lot of responsibility for a kid to make sure everything’s intact and they're not going to run into some trouble when they're out somewhere. The positive is that modern medicine has allowed them to be alive."
Finding NormalDarla says that her daughters do everything they can to participate in activities like other kids their age.
"Mackenzie wanted to buy Rollerblades or a skateboard," says Darla. "I couldn't let her do it. She was bummed for a little while, but she got over it and found some other interest, and to me that is amazing. We talked about a bike. I'm not sure we sold her on the bike yet."
Macey speaks up for her sister: "Are you out of your mind?" she says to Darla. "How are we going to ride bikes?"
"It's possible," Darla says. "We're going to make it happen."
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