Today is Irena Sendler's 97th birthday. She is frail now, but as a young woman in wartime Poland, she was a portrait of strength -- almost single-handedly defying arrest, torture and the threat of death to save 2,500 Jewish children from almost certain death in Nazi death camps.
She is the last surviving person from the group she worked with that ran an underground network to save these children, and she spoke with ABC News in Warsaw, in a rare interview about her decision to take such a risk.
"When the war started, all of Poland was drowning in a sea of blood, but most of all it affected the Jewish nation. And within that nation it was the children who suffered most. That's why we needed to give our hearts to them," Sendler said.
And in saving these children she gave them a second chance at life. As German troops swept through the Warsaw ghetto, burning Jewish homes and sending entire families to death camps, Sendler created a secret underground network to sneak children to safety.
Across Warsaw, Sendler organized 10 "care centers" -- underground institutions staffed by 20 to 30 volunteers, mostly women. Their task was to provide midwives who'd sneak into the ghetto to receive Jewish newborns, and then keep them in hiding until they could find them foster parents or hide them away in convents.
Many convents ran foster homes during the war and Jewish children stood a good chance of surviving there, disguised as non-Jewish orphans of the war.
"I have to share all credit with the 30-odd people who worked with me," she said. "Alone, I couldn't have done it. It was 30 brave people. None of them are alive today. One of my helpers was executed. I'm the only survivor."
Elzbieta Ficowska was 6-months old in 1942 when she was smuggled out of the Warsaw ghetto in a pile of bricks. Her parents gave her a sedative to keep her from sobbing and a silver spoon, which she still keeps to this day. Her parents died in the death camps, but she survived thanks to Sendler.
"Irena represents the often forgotten truth, that no one should be indifferent," Ficowska said. "Irena became a symbol. A symbol of something very good. A symbol of undeniable authority. In today's world of eroding values in which role models crumble one after another, it's particularly the young who need people like Mrs. Sendler."
When Katarzyna Meloch's parents were killed, Sendler smuggled her to a convent, where nuns protected her and dozens of other Jewish children.
"Irena is a wonderful person, the wonderful leader of a wonderful cause," Meloch said.
Today's Warsaw still bears the landmarks of Sendler's life-saving work. There is the corner store where Sendler hid children in the basement, and the apple tree still stands where Sendler buried jars stuffed with documents identifying the children she saved, all within plain sight of the German army barracks.
Many children, like Elzbieta, were never told who saved them and how until they were adults. Now they're fighting to give Sendler recognition, nominating her for the Nobel Peace Prize. They had also hoped to hold a large public birthday celebration for her today, but Sendler's failing health made that impossible.
Sendler herself shies away from the attention, not just out of modesty but real disappointment.
"After the Second World War, it seemed that humanity understood something and that nothing similar would happen again," Sendler said. "Humanity has understood nothing. Religious, tribal, national wars continue. The world continues to be in a sea of blood."
But then, she added, "The world can be better if there's love, tolerance and humility." And that thought made her smile.