WASHINGTON — For more than 40 years, President George H.W. Bush carried a gold medallion in his wallet reading, "For the Love of Robin."
It was a reminder of a tragedy that has shaped the Bush family — a tragedy put in the spotlight this week after Bush was seen with a bald head, shaved in solidarity with a leukemia-stricken 2-year-old boy.
In 1953, a few weeks after her second son, Jeb, was born in February, Barbara Bush noticed that her daughter, Robin, was behaving strangely.
"Robin woke one morning and was undecided as to what to do," says an online memorial for the Bushes' second child, born Dec. 20, 1949, as Pauline Robinson Bush. "She stated that she might just lie on the grass and watch the cars go by or maybe just stay in bed."
Thinking that the child might have spring fever, her mother took her to a doctor. The next day, she and her husband received the news: Robin had leukemia, a disease associated with an abnormal increase of immature white blood cells.
The doctor said she had two weeks to live and advised letting Robin, as the family called her, "quietly slip away while keeping her comfortable and loving her."
The Bushes refused and took her to the Memorial Sloan-Kettering Hospital in New York City.
"They took bone marrow tests, which were painful," Barbara Bush said in a 2012 interview with the "Today Show." "A lot of blood. They put her on chemo, and poor Gampy, every time she got a blood transfusion he'd have to leave the room," she said, referring to her husband.
After six months of treatment, Robin died Oct. 11, 1953, two months before her 4th birthday.
"I was combing her hair and holding her hand," Barbara Bush told the "Today" show. "I saw that little body, I saw her spirit go."
Over the years, members of the Bush clan have reflected publicly on how the girl's death affected their lives, bringing them closer as a family and driving an interest in medical research.
In his 1987 biography, "Looking Forward," Bush said prayer helped him and his wife through Robin's treatment: "Barbara and I sustained each other; but in the end, it was our faith that truly sustained us, as gradually but surely, Robin slipped away."
During the ordeal, then 28-year-old Barbara Bush's hair turned white. The family donated Robin's body to medical research, a novel decision for the time, but one they made in hope of helping find a cure.
After Robin's death, Bush wrote a lyrical letter to his mother about wanting to have another daughter.
"We need a legitimate Christmas angel, one who doesn't have cuffs beneath her dress. You have to be a father to know this," he wrote. "We need a little one who can kiss without leaving egg or jam or gum. We need a girl. We had one once..... But she is still with us. We need her and yet we have her."
In a 2010 interview with Larry King, Bush wiped away tears as King read parts of the letter aloud.
Members of the Bush family channeled their grief by raising awareness and money for leukemia research through the Bright Star Foundation, founded in Robin's memory.
In 2004, the M.D. Anderson Cancer Center in Houston recognized their work by opening the Robin Bush Child and Adolescent Clinic.
On Wednesday, Bush shaved his head in solidarity with Patrick, the 2-year-old son of a Secret Service agent assigned to Bush's detail.
Patrick, whose last name has been withheld at the request of the family, was diagnosed with leukemia this spring. While undergoing chemotherapy treatments, he has begun to lose his hair.
Members of Bush's Secret Service detail set up a website and organized a motorcycle run to benefit Patrick and his family.
Smiling and holding Patrick on his lap, Bush joined the members of his Secret Service detail who had also shaved their heads in support of Patrick.
Better technology, as well as cells and DNA preserved from patients treated in the 1960s, has improved outcomes for children. St. Jude Children's Research Hospital estimates the survival rate for the most common type of childhood leukemia has increased from 4% in 1962 to 94% today.
"It made Gampy and me feel that something good is coming out of this precious little life," Barbara Bush told the "Today Show." Robin was buried in Greenwich, Conn. Her grave, with its small headstone that simply reads, "Robin," was moved in 2000 to a small cemetery at the George Bush Presidential Library in College Station, Texas — where her parents will also one day be interred.
In the interview, granddaughter Jenna Bush Hager remarked how Bush has said he expects Robin to be the first person he sees after he dies.
Barbara Bush agreed, saying they had both thought of Robin often in recent years.
"We are getting older, and Robin to me is like a joy, an angel — not a sadness or sorrow," she said. "[Robin] is who he'll see first."