ESHHAR, ISRAEL – Idit Harel Segal was turning 50, and she had chosen a gift: She was going to give one of her own kidneys to a stranger.

The kindergarten teacher from northern Israel, a proud Israeli, hoped her choice would set an example of generosity in a land of perpetual conflict. She was spurred by memories of her late grandfather, a Holocaust survivor, who told her to live meaningfully, and by Jewish tradition, which holds that there's no higher duty than saving a life.

So Segal contacted a group that links donors and recipients, launching a nine-month process to transfer her kidney to someone who needed one.

That someone turned out to be a 3-year-old Palestinian boy from the Gaza Strip.

"You don't know me, but soon we'll be very close because my kidney will be in your body," Segal wrote in Hebrew to the boy, whose family asked not to be named due to the sensitivities over cooperating with Israelis. A friend translated the letter into Arabic. "I hope with all my heart that this surgery will succeed and you will live a long and healthy and meaningful life."

What unfolded over the months between Segal's decision and the June 16 transplant caused deep rifts in the family. Her husband and the oldest of her three children, a son in his early 20s, opposed the plan. Her father stopped talking to her.

To them, Segal recalled, she was unnecessarily risking her life. The loss of three relatives in Palestinian attacks, including her father's parents, made it even more difficult.

When she learned the boy's identity, she kept the details to herself for months.

"I told no one," Segal recalled. "I told myself if the reaction to the kidney donation is so harsh, so obviously the fact that a Palestinian boy is getting it will make it even harsher."

Israel has maintained a tight blockade over Gaza since Hamas, an Islamic militant group that opposes Israel's existence, seized control of the area in 2007.

The bitter enemies have fought four wars since then, and few Gazans are allowed to enter Israel.

Matnat Chaim, a nongovernmental organization in Jerusalem, coordinated the exchange, said the group's chief executive, Sharona Sherman.

The case of the Gaza boy was complicated. To speed up the process, his father, who was not a match for his son, was told by the hospital that if he were to donate a kidney to an Israeli recipient, the boy would "immediately go to the top of the list," Sherman said.

On the same day his son received a new kidney, the father donated one of his own — to a 25-year-old Israeli mother of two.

In some countries, reciprocity is not permitted because it raises the question of whether the donor has been coerced. The whole ethic of organ donation is based on the principle that the donors should give of their own free will and get nothing in return.

For Segal, the gift that had sparked such conflict in her family accomplished more than she hoped. Her kidney has helped save the boy's life, generated a second donation and established new links between members of perpetually warring groups in one of the world's most intractable conflicts. She said she visited the boy on the eve of his surgery and maintains contact with his parents.

On the eve of her surgery, her father called. Then, she told him that her kidney was going to a Palestinian boy.

For a moment, there was silence.

"Well," he finally said, "he needs life, also."