Kerry and David Mills assumed their family was complete three years ago when they adopted a daughter, Esther, from China.
The Mills, at the time the parents of two young boys, had never even thought of adoption until one day in 2013 when Kerry brought it up.
"It was a Sunday afternoon and we were coming out of church and getting into the car and out of the blue, we’d never talked about it before, Kerry said, 'What would you guys think about adopting a girl?,'" recalled David Mills, a lieutenant colonel in the U.S. Air Force. "I think we surprised her because we all said yes."
Three years later the family, who lives near Richmond, Virginia, brought home Esther, who was six at the time and faced medical complications.
"All that we knew at the time was Esther was born with spina bifida and she’d had a surgery and it had been repaired. That was about all we knew," said David Mills. "It was not until we brought her to America and had all the medical testing done here that we learned she had chronic kidney disease."
The Mills got Esther the medical treatment she needed as she blended into their family, overcoming obstacles like homesickness and a language barrier in addition to doctors' appointments and two surgeries.
(MORE: Couple adopts 15-month-old twins they fostered at 1-month-old)"She just dove right into our family and has been that way ever since," said Kerry Mills. "She did some mourning there in the beginning of the changes ... but she really attached quickly and learned the language quickly."
The Mills family focused on Esther, now 9 and in second grade, without thinking they would adopt another child. But they still stayed tapped into an adoption-focused Facebook group, where one day last year they were surprised to see a photo of a 13-year-old girl with the same kidney condition and spina bifida diagnosis as Esther.
"We were surprised to see her picture, and then what really surprised us is she had the same medical condition," said Kerry Mills. "We thought we’ve already learned so much about kidney disease, we could totally apply that to help another kid."
In the case of this adoption, the couple was working against a deadline. At 13 years old, the girl, Mia, was just one year younger than the age of 14 when children in China age out of the adoption system.
(MORE: Micro preemie to spend Christmas at home after 268 days in NICU)"We first saw Mia’s picture in October 2018 and started the adoption process in December and then nine months later adopted her," said Kerry Mills, who traveled with Esther and one of her sons to bring Mia home to the U.S. in September.
A typical adoption can take anywhere from 18 to 24 months to complete, according to Pam Devereux, CEO of Gift of Adoption, a nonprofit organization that provided financial support to the Mills family for Mia's adoption through its RAREis Adoption Fund that focuses on kids with rare diseases.
"For them the adoption was expedited and almost life-saving, but it meant the financial cost was something on their shoulders right away," said Devereux. "We were part of their story in getting Mia home."
Mia was diagnosed by doctors in the U.S. with kidney failure, otherwise known an end-stage renal disease. She is currently on the waiting list for a kidney transplant, an option not available to her in China, according to Kerry Mills.
"She was on dialysis for five years in China," she said. "Dialysis for her was three times a week for four hours at a time, so she only went to school two times a week."
Mia is now attending school via a co-op that allows her to continue her dialysis treatments. The Mills are also being trained to do dialysis at home while Mia waits for a kidney.
Just three months into being sisters, Mia and Esther have developed a "pretty good bond" based on their shared heritage and medical experience, according to David Mills.
The family -- including sons Luke, 16, and Braden, 12 -- has spent the past month introducing Mia to their family holiday traditions.
It’s the best gift you can give, the gift of family.
"Our family traditions like doing gingerbread houses are completely new for Mia so it's really fun," said Kerry Mills. "She's watching people bring a live [Christmas] tree into the house and hang socks on the mantel, so Mia has asked a lot of questions."
The couple hopes their story of adoption will inspire others to look at how they can expand their own hearts and homes to kids in need.
"We never talked about having a big family. It just happened and it's ended up being the best blessing," said Kerry Mills. "It just opens your world and your eyes to all the possibilities of what you can do and what you can give."
"We are very far from being perfect. We don’t have it all together. We don’t always have our dishes done. We’re not high income earners. We argue," said David Mills. "And I’ve come to learn that that is completely fine."
"It’s the best gift you can give, the gift of family," he said.