"They approach you at a time after you have received the tragic news and it has to be done in a timely manner," she said. "It was always something I knew we were going to do and I know it has to be done immediately. Had they not asked, we would have offered."
The United Network for Organ Sharing, the nonprofit group that allocates organs once they are recovered and matches them with recipients, has said in a prepared statement that the family of Christina-Taylor has set a positive example for others.
"We are grateful for everyone who chooses to save and enhance the lives of others through organ, eye and tissue donation," said Charles Alexander, UNOS president and CEO of The Living Legacy Foundation of Maryland. "We hope their example inspires others to respond by making a commitment to donate."
An estimated 110,000 Americans are on a waiting list for an organ transplant. Of those, 90 are under the age of 1; 1,528 are aged 1 to 5; 350 are aged 6 to 10; and 785 are 11 to 17, according to UNOS.
In 2009, the last year for which there is data, 28,463 transplants were performed. Of those, 331 were for children under the age of 1; 592 for children 1 to 5; 315 for those 6 to 10; and 780 for children 11 to 17.
One donor can help up to eight people with various organs. The greatest need for all age groups are donated kidneys, followed by the liver. Adults can also donate a part of those organs to children.
Of the estimated 8,000 deceased organ donors last year about 800 were children, according to UNOS.
The decision a parent must make can be guided by their knowledge of the child.
"A lot of times an older kid who has learned about organ donation in school and has told his parents, makes it easier for them because they knew what he wanted," said UNOS spokesman Anne Paschke. "They may say. 'My kid was very giving and so I think that's what he would have wanted.'"
As for the Greens, they understand the donor decision may be more difficult for some than others, especially when it involves a child.
"If you are put in a situation where it's your mother, brother, sister or husband, we don't think twice about [organ donation]," she said. "Certainly I understand it's a difficult decision and a personal choice and I don't want to judge people who don't want to do it."
When her mother died, Roxanna Green said the family discussed the possibility and even Christina was in on the decision.
"I understand it's a personal choice, but in our family, we are all about helping others and giving," she said.
Roxanna Green said that her daughter was not only passionate about helping others in the political realm -- the third-grader was on her school's student council -- but Christina-Taylor was interested in medicine as well.
"She wanted to be a vet or a doctor and so this was right down her alley," said her mother. "She would not think twice about helping animals that were hurt or friends that were hurt by visiting them. She was all about helping. This was not a hard decision at all for us to come to."
Roxanna Green said one day she might like to meet the donors who were saved by her daughter's organs.
"I don't want to invade on their privacy, but you know I would be happy to tell them it would be an honor for us," she said. "Our daughter is looking down from heaven, happy to give a small gift to help save someone's sight or help their life. She was a leader and a child older beyond her years. She is proud to do this."