Rose Marie Kennedy was born at her parents' home in Brookline, Massachusetts. She was the third child and first daughter of Joseph P. Kennedy Sr. and Rose Fitzgerald. She was named after her mother and was commonly called Rosemary or Rosie. During her birth, the doctor was not immediately available and the nurse ordered Rose Kennedy to keep her legs closed, forcing the baby's head to stay in the birth canal for two hours. The action resulted in a harmful loss of oxygen. As Rosemary began to grow, her parents noticed she was not reaching the basic development steps an infant or a toddler normally reaches at a certain month or year. At two years old, she had a hard time sitting up, crawling, and learning to walk.