Kiersten Miles of New Jersey had been nannying for only three weeks when she made the decision.
The baby girl for whom Miles had started caring had a rare, life-threatening liver disease in which her liver's central bile duct had been inexplicably destroyed and bile was building up into her liver, the baby's mother said.
The whites of her eyes were gray.
Her skin was yellow.
And some doctors predicted that the child might not live past her second birthday.
But 22-year-old Miles had a solution: She would give the girl a piece of her own liver.
"Especially for a baby who can't really ask for help, it didn't seem like that much of a sacrifice," she told The Washington Post, "because I'd be saving a life."
Earlier this month, Miles donated a portion of her liver to Talia Rosko - a priceless gift that the child's family says saved the 16-month-old's life.
George and Farra Rosko, of Jackson, New Jersey, hired Miles in summer 2016 to take care of Talia, as well as Talia's two older siblings.
Just weeks after Miles took the job, she said, she started thinking about Talia's condition and how she might be able to help. She said she started researching living organ donation because "I was just curious, I guess," and she thought she might be a good candidate because she knew her blood type was O, which is compatible with all other blood types, according to the American Red Cross.
Almost immediately, Miles said, she knew she wanted to see if she could do it.
She said she talked to her own mother, then prepared to sit down with Talia's parents.
"I was nervous for some reason - I'm not sure why," Miles said about the conversation with Farra Rosko. "I just told her I had done some research, and I wanted to fill out the paperwork to see if I was a match."
Watch: Kiersten and Talia's journey
The first thing Rosko asked her was whether she had spoken to her own parents about it.
"This is a serious thing," Rosko said she told Miles. "This is not like donating blood."
"I was very taken aback," Rosko told The Post. "I didn't know that she was this selfless - I've come to find out that this is who she is. She really is an angel on earth; I know that sounds silly, but she really is."
Over the next several months, Miles underwent rounds of testing to determine whether she was eligible to be Talia's donor. When she discovered she was, she made a "surreal" sacrifice, Rosko said.
When Talia was 9 weeks old, Rosko said, her pediatrician noticed that her eyes "were off" and sent her to a specialist for further testing and a liver biopsy. It was determined that the infant had biliary atresia, "a life-threatening condition in infants in which the bile ducts inside or outside the liver do not have normal openings," according to National Institute of Diabetes and Digestive and Kidney Diseases.
With biliary atresia, bile becomes trapped, builds up, and damages the liver. The damage leads to scarring, loss of liver tissue, and cirrhosis. Cirrhosis is a chronic, or long lasting, liver condition caused by scar tissue and cell damage that makes it hard for the liver to remove toxins from the blood. These toxins build up in the blood and the liver slowly deteriorates and malfunctions. Without treatment, the liver eventually fails and the infant needs a liver transplant to stay alive.
Rosko said that Talia's central bile duct was "obliterated" and that she was eventually put on a transplant list, though Rosko explained that it can take much more time to find a liver for a small child.
The Roskos met Miles about the same time their daughter was placed on the list.
On January 11, medical teams removed a portion of Miles' liver at the Hospital of the University of Pennsylvania and rushed it next door to the Children's Hospital of Philadelphia, where they implanted it in Talia.
"Once they had taken [the piece of] the liver out, they told us," Rosko said. "That's a pretty powerful moment. When it was happening, it was surreal."
It was a moment that Rosko said she never really expected to come.
"We didn't even know her," Rosko said of Miles. "I thought it was wonderful that she offered, but I didn't really think it would go through. It's not something that people do every day."
But it did - and when Talia woke up, she first asked for her mum.
"She looked up and said, 'Mama,' " Rosko said. "It was miraculous."
Not far away, Miles was also recovering, from her liver donation.
She said the most emotional moment for her was shortly after she woke up from surgery. She said she had been concerned that something would go wrong with her liver and it wouldn't work inside Talia's small body.
"I don't know if it was all the emotions building up over time, but I asked one of the surgeons if I could see Talia," Miles said. "He told me that I could definitely see her in the next couple of days. He said she was doing great. And when he left, I just started bawling.
"I think I was just really happy and really relieved at the same time."
Kiersten and Talia are reunited
Later on, when they reunited, Rosko said, "It was a magical moment."
"When I saw Kiersten come in, my heart skipped a beat," Rosko said.
"It was like a movie star coming in," she said of Miles. "Even the doctors and the nurses were saying, 'Is this your live donor? Oh, my God, tell me the story.' Everybody was just so taken aback by her generosity."
Miles said when she saw Talia, "It just reminded me why I did it all."
Talia's mother said the baby girl will be able to taper off medications over the next year, though she will likely have to take anti-rejection drugs the rest of her life.
Miles, a college student studying special education, said she has a five-inch scar and can never again donate part of her liver, even if it's a perfect match for one of her own family members in the future.
But she said she doesn't mind.
After their surgeries, she said, Talia smiled at her, and "it just made everything worth it."
She said she has been overwhelmed with the response she has gotten, even from strangers.
"I'm overwhelmed by the outpouring of love and support I've received over the past few weeks and continue to receive," Miles wrote on Facebook on Saturday. "So many people, many whom I don't even know, have shared the story of my donation to Talia. I've tried to at least 'like' every post I've seen but I just wanted to say THANK YOU! Thank you so, so much. Every share spreads more awareness about living liver donation and organ donation in general. Once again, I really appreciate all of the shares and messages. They mean so much to me. You all are the absolute best!"
Rosko said that she doesn't know what would have happened to her daughter if Miles hadn't come into their lives when she did.
"I think people need to know that prayer does work, angels do exist and miracles happen every day," she said. "I don't know where we would be without Kiersten."