Caroline Kennedy's Forgotten Tragedy

As Caroline Kennedy becomes the next Ambassador to Japan, INSIDE EDITION reports on her new chapter and a forgotten chapter of her baby brother.

Caroline Kennedy's family was by her side for her big day in Washington with her husband, Edwin Scholssberg, and two of her three chlidren, 23-year-old Tatiana and 20-year-old Jack, who bears a remarkable resemblance to his late uncle, JFK Jr.

New York Senator Chuck Schumer introduced Caroline and made a poignant reference to her storied family history, saying, "Caroline Kennedy grew up in the public eye. We as a nation grew up with her sharing her joys as well as her heartbreaks."

We're all familiar with the long list of Kennedy sorrows. But there's one forgotten tragedy not many people know about. Caroline and John-John had a baby brother named Patrick, born three months before their father's assassination in 1963.

Christopher Andersen is the author of These Few Precious Days: the Final Year of Jack with Jackie. 

Anderson told INSIDE EDITION, "I really think she felt that Patrick was the answer to all of her problems. That's what makes it so sad."

Jackie Kennedy went into labor five-and-a-half weeks early while the first family was vacationing on Cape Cod. But tiny Patrick was suffering from respiratory distress syndrome. The nation was transfixed by the unfolding medical drama.

Jackie held her son's hand for 10 minutes before he was transferred to Boston Children's Hospital - the last time she would see him alive.

Jackie once described the moment that JFK told her about their son's death in an audio recording.

She said, "He came back from Boston to me in the hospital, and he walked in the morning about eight in my room and just sobbed and put his arms around me."

"Jackie couldn't attend [the funeral]. She was still sick so she was in the hospital back in Cape Cod. At one point at the end of the funeral, Jack would not let go of the tiny little coffin containing his son. He held it in his arms and refused to move," Andersen said.