Ritta and Christina were born in Sassari, Sardinia, on March 3, 1829, to Maria Teresa Parodi, a 32-year-old mother of eight. The Parodis were quite poor, but recognized the potential of their extraordinary babies and spent their savings on a trip to France. There, they sought to exhibit the twins publicly but were repeatedly denied permission to do so by officials in every town they visited. Their parents succeeded somewhat in exhibiting them in private to physicians, who were constantly uncovering the babies and exposing them to the cold. Ritta, who was smaller and weaker than Christina, had suffered poor health since birth, and frequently became sick on the journey from city to city, though she usually recovered upon arrival. After arriving in Paris, however, Ritta seemed fatigued. Her health began to decline sharply until, on November 23, 1829, while suckling from their mother, she expired. Christina, who was never affected by her sister's illnesses, continued to nurse for a few moments before she, too, died.
During their short lives, the twins displayed very different personalities, with Ritta inclined to be sad and subdued while Christina was often happy and laughing. Their nervous systems were not connected and a pinch or poke on Ritta's side of the body would not be felt by Christina. They had separate stomachs and were thus hungry at different times. On autopsy it was found that Ritta's heart was on the right side of her body, a condition called situs inversus which is not fatal on its own, but she also had several holes in her heart. The twins' skeleton and a plaster cast of their body are allegedly in the possession of the Natural History Museum in Paris.