So what's her story, you ask? I'll tell you, but first:

Warning: this will depress the hell out of you, so gird yourself or flee from here at once in search of a feel-good YouTube video of kittens and puppies being best friends.

Don't say I didn't warn you...

Rosemary's entry into the world was as troubled as what came after it. The year was 1918. World War I was still raging and Spanish influenza was making its way around the world, killing millions. Because so many people in the Boston area needed care, the family physician wasn't able to immediately pay the Kennedys a house call to deliver Rosemary. The attending nurse, who was fully capable of delivering the baby, ordered Rose to keep her legs closed until the doctor arrived. When this didn't work, the nurse pushed the baby's head back into the birth canal and held it there for two hours.

The effects of this decision only became clear as Rosemary grew older. Every infant milestone -- crawling, standing, walking, speaking -- arrived later than it should have. This delay continued at school; teachers advised that she repeat kindergarten and then the first grade too.

Joe and Rose Kennedy, who both came from overachieving families, were known for placing high academic and physical expectations on their children, and they made no exception for Rosemary. Both parents believed that Rosemary could be "cured" through a combination of holding her to the same standard as her siblings, specialized education and experimental injections. Despite their best efforts, Rosemary would never advance intellectually past the fifth grade.

In the early 20th century, many elites were swept up in the eugenics movement, an ideology marked by a belief that some groups -- immigrants, people of color, the poor and the disabled -- had a "bad gene" and should not be allowed to breed. The Catholic Church, which was a major part of the family's way of life, refused Communion and Confirmation to the disabled. If the Kennedys were to be honest about Rosemary's challenges, their friends and other influential people would blame them for passing along defective genes and their religion would shun them and their daughter. Worried that the truth about Rosemary would sully the family reputation or complicate their political aspirations, Rosemary was sent away to various schools and her parents did their best to keep her condition a secret.

No one was more frustrated by not being able to make her parents proud than Rosemary. Her desire to please them can be felt in letters to her father: "I would do anything to make you so happy. I hate to [disappoint] you in any way. Come to see me very soon. I get very lonesome everyday."

Learning challenges and parental pressures aside, Rosemary was a very social, amiable person, known for her big smile. She loved fashion, swimming, and going out on the town. Her older brothers, Joe Jr. and John, would often accompany Rosemary to dances. "They waltzed her around the ballrooms, brought her punch, stood with her and shared a quiet laugh, stayed with her so that she appeared not different at all."

Despite this compassion for his sister, Joe Jr. would later become radicalized on a trip to Germany in 1934 and adopt less than tender attitudes towards "undesirables," including people with disabilities. He wrote home to his father: "[Hitler] has passed the sterilization law which I think is a great thing. I don't know how the Church feels about it, but it will do away with many of the disgusting specimens of men which inhabit this earth." His father seemed to agree in his reply: "I think your conclusions are very sound."

In 1938, FDR appointed Rosemary's father as ambassador to the United Kingdom. The entire family relocated and it wasn't long before Rosemary and her younger sister Kathleen were presented to the King and Queen in a debutante "coming out" to high society. Despite only having two weeks to prepare (most women dedicated months), Rosemary aced all the customs she had been taught and, apart from a minor stumble in front of the royals, had a perfect evening of socializing and dancing with high-profile, eligible bachelors. British newspapers were enamored with Rosemary and her dress, and favored her greatly over her sister in their coverage of the events, much to the dismay of her mother.

As Rosemary settled into life abroad, her circumstances continued to improve. Her parents enrolled her in a Montessori school, which traded the competitive qualities of Rosemary's home life for a more reassuring, confidence-building approach. Rosemary flourished, academically and socially. Her lead educator wrote her parents that Rosemary had made "remarkable progress" and that there had been "a great change in her lately." After visiting her, Joe Sr. agreed: "She is happy, looks better than she ever did in her life, is not the slightest bit lonesome."

Just as Rosemary was finally finding comfort and happiness, history intervened. Germany was getting more and more aggressive on the continent and Rosemary had to first be moved out of London and then out of England entirely.

Back in the States, Rosemary became more rebellious, her behavior more erratic. "Every day there would be fights where Rosemary would use her fists to hit and bruise people." She was known to break out of school to roam the streets of D.C. Rosemary's actions worried her parents. The Lindbergh tragedy had made many prominent families paranoid about their children being targeted in kidnappings or worse. Wrought with stress over Rosemary's safety and their social standing, Joe Sr. and Rose reached a breaking point and began to desperately seek surgical solutions.

Joe Sr. had heard news of a new surgery called a prefrontal lobotomy, which was performed as therapy for people with mental disorders, LGBT people, women who were considered too sexual, criminals and addicts. The surgery had only been practiced for three years in the States. 80% of the patients were women. Evidence suggested that this experimental surgery was risky, unreliable, often damaging and sometimes lethal (9% of all patients died). The American Medical Association strongly advised against the practice until further studies could be done. Despite all this, Joe Sr. arranged for Rosemary to undergo the operation without consulting his wife or anyone else in the family.

Rosemary's head was shaved. She was strapped to an operating table and kept awake for the surgery. The doctors asked her to sing songs like "God Bless America," recite the Lord's Prayer and tell stories, as they cut into her brain, only stopping after she had gone quiet. "They knew right away that it wasn't successful." The attending nurse is said to have been so traumatized by what she saw that she quit her profession.

What was once a manageable behavioral problem was now something far worse. Rosemary, then 23-years-old, had regressed to the state of a two-year-old, losing her ability to walk and speak. Joe Sr. immediately sent Rosemary to a psychiatric hospital in upstate New York, much to the confusion of her siblings and others. "[Why] after all these years, did she have to be institutionalized now? And why couldn't any of the family see her?"

Joe Sr. allegedly told his wife it would be best for her not to visit Rosemary so she could get "accustomed" to her new living arrangement. They told everyone else that she was off studying to be a teacher or getting involved in social work. Eunice, the sibling Rosemary was closest to, said that she didn't know where Rosemary was for over a decade. In letters to the family, Joe Sr. kept up a vague facade that Rosemary was "getting along quite happily," never once mentioning the surgery. After 1944, all mentions of Rosemary in family letters stopped.

By 1948, John had been elected to the House of Representatives and had aspirations for higher offices. Joe Sr. started to worry about the secret of Rosemary getting out and spoiling things, so he made arrangements to have Rosemary relocated to an institution in Wisconsin, where she would live for the remaining 56 years of her life. He never visited.

In 1958, John secretly went to see Rosemary and only then did he realize the severity of what had been done to her. This traumatic revelation inspired him to eventually use his power as President to enact several pieces of legislation that funded research and programs for the disabled.

Eunice was also doing what she could to enact change, first dedicating money from the Kennedy Foundation to research, then founding Camp Shriver, a retreat for disabled kids, and eventually creating the Special Olympics. These efforts, coupled with John's political actions, changed America's public perception of the disabled in a major way. In Ted Kennedy's words, she "taught us the worth of every human being."

Around this time, Rose decided to visit Rosemary. It had been over 20 years. Upon seeing her mother after all this time, Rosemary became very upset and "recoiled" from her.

By the '70s, Rosemary began to attend family vacations. Being around her mother was stressful for her, but her nephews and nieces did their best to create a supportive, loving environment, filled with desserts, swimming, card games, music and other things Rosemary loved. She ended up making quite the impression on Eunice's sons. Anthony Shriver, who built a room for Rosemary in his home, founded Best Buddies International, a non-profit that provides disabled individuals with a mentor, as well as employment opportunities. And his brother, Timothy, took over the role of Special Olympics CEO from his mother.

Rosemary lived out her days in a cottage specifically built for her and her caretakers on the grounds of the Wisconsin institution. She was popular with the staff and other residents, enjoyed swimming, going out for joy rides, playing card games, and spoiling her pets (a canary named Skippy and a poodle named Lollie). In 2005, Rosemary died of natural causes with her four surviving siblings by her side.

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